lesson 23: antiderivatives (slides)

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. . SecƟon 4.7 AnƟderivaƟves V63.0121.001: Calculus I Professor MaƩhew Leingang New York University April 19, 2011

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Page 1: Lesson 23: Antiderivatives (slides)

..

Sec on 4.7An deriva ves

V63.0121.001: Calculus IProfessor Ma hew Leingang

New York University

April 19, 2011

Page 2: Lesson 23: Antiderivatives (slides)

Announcements

I Quiz 5 on Sec ons4.1–4.4 April 28/29

I Final Exam Thursday May12, 2:00–3:50pm

I I am teaching Calc II MW2:00pm and Calc III TR2:00pm both Fall ’11 andSpring ’12

Page 3: Lesson 23: Antiderivatives (slides)

ObjectivesI Given a ”simple“ elementaryfunc on, find a func on whosederiva ve is that func on.

I Remember that a func onwhose deriva ve is zero alongan intervalmust be zero alongthat interval.

I Solve problems involvingrec linear mo on.

Page 4: Lesson 23: Antiderivatives (slides)

OutlineWhat is an an deriva ve?

Tabula ng An deriva vesPower func onsCombina onsExponen al func onsTrigonometric func onsAn deriva ves of piecewise func ons

Finding An deriva ves Graphically

Rec linear mo on

Page 5: Lesson 23: Antiderivatives (slides)

What is an antiderivative?

Defini onLet f be a func on. An an deriva ve for f is a func on F such thatF′ = f.

Page 6: Lesson 23: Antiderivatives (slides)

Who cares?Ques on

Why would we want the an deriva ve of a func on?

Answers

I For the challenge of itI For applica ons when the deriva ve of a func on is known butthe original func on is not

I Biggest applica on will be a er the Fundamental Theorem ofCalculus (Chapter 5)

Page 7: Lesson 23: Antiderivatives (slides)

Hard problem, easy check

Example

Find an an deriva ve for f(x) = ln x.

Solu on???

Page 8: Lesson 23: Antiderivatives (slides)

Hard problem, easy check

Example

Find an an deriva ve for f(x) = ln x.

Solu on???

Page 9: Lesson 23: Antiderivatives (slides)

Hard problem, easy check

Example

is F(x) = x ln x− x an an deriva ve for f(x) = ln x?

Solu on

ddx

(x ln x− x) = 1 · ln x+ x · 1x− 1 = ln x

"

Page 10: Lesson 23: Antiderivatives (slides)

Hard problem, easy check

Example

is F(x) = x ln x− x an an deriva ve for f(x) = ln x?

Solu on

ddx

(x ln x− x) = 1 · ln x+ x · 1x− 1 = ln x"

Page 11: Lesson 23: Antiderivatives (slides)

Why the MVT is the MITCMost Important Theorem In Calculus!

TheoremLet f′ = 0 on an interval (a, b). Then f is constant on (a, b).

Proof.Pick any points x and y in (a, b) with x < y. By MVT there exists apoint z in (x, y) such that

f(y) = f(x) + f′(z)(y− x)

But f′(z) = 0, so f(y) = f(x). Since this is true for all x and y in (a, b),then f is constant.

Page 12: Lesson 23: Antiderivatives (slides)

Functions with the same derivativeTheoremSuppose f and g are two differen able func ons on (a, b) withf′ = g′. Then f and g differ by a constant. That is, there exists aconstant C such that f(x) = g(x) + C.

Proof.

I Let h(x) = f(x)− g(x)I Then h′(x) = f′(x)− g′(x) = 0 on (a, b)I So h(x) = C, a constantI This means f(x)− g(x) = C on (a, b)

Page 13: Lesson 23: Antiderivatives (slides)

OutlineWhat is an an deriva ve?

Tabula ng An deriva vesPower func onsCombina onsExponen al func onsTrigonometric func onsAn deriva ves of piecewise func ons

Finding An deriva ves Graphically

Rec linear mo on

Page 14: Lesson 23: Antiderivatives (slides)

Antiderivatives of power functionsRecall that the deriva ve of apower func on is a powerfunc on.Fact (The Power Rule)

If f(x) = xr, then f′(x) = rxr−1.

So in looking foran deriva ves of powerfunc ons, try powerfunc ons!

..x

.

y

.

f(x) = x2

.

f′(x) = 2x

.

F(x) = ?

Page 15: Lesson 23: Antiderivatives (slides)

Antiderivatives of power functionsRecall that the deriva ve of apower func on is a powerfunc on.Fact (The Power Rule)

If f(x) = xr, then f′(x) = rxr−1.

So in looking foran deriva ves of powerfunc ons, try powerfunc ons!

..x

.

y

.

f(x) = x2

.

f′(x) = 2x

.

F(x) = ?

Page 16: Lesson 23: Antiderivatives (slides)

Antiderivatives of power functionsRecall that the deriva ve of apower func on is a powerfunc on.Fact (The Power Rule)

If f(x) = xr, then f′(x) = rxr−1.

So in looking foran deriva ves of powerfunc ons, try powerfunc ons!

..x

.

y

.

f(x) = x2

.

f′(x) = 2x

.

F(x) = ?

Page 17: Lesson 23: Antiderivatives (slides)

Antiderivatives of power functionsRecall that the deriva ve of apower func on is a powerfunc on.Fact (The Power Rule)

If f(x) = xr, then f′(x) = rxr−1.

So in looking foran deriva ves of powerfunc ons, try powerfunc ons!

..x

.

y

.

f(x) = x2

.

f′(x) = 2x

.

F(x) = ?

Page 18: Lesson 23: Antiderivatives (slides)

Antiderivatives of power functionsExample

Find an an deriva ve for the func on f(x) = x3.

Solu on

I Try a power func on F(x) = axr

I Then F′(x) = arxr−1, so we want arxr−1 = x3.

I r− 1 = 3 =⇒ r = 4

, and ar = 1 =⇒ a =14.

I So F(x) =14x4 is an an deriva ve.

I Check:ddx

(14x4)

= 4 · 14x4−1 = x3"

I Any others?

Yes, F(x) =14x4 + C is the most general form.

Page 19: Lesson 23: Antiderivatives (slides)

Antiderivatives of power functionsExample

Find an an deriva ve for the func on f(x) = x3.

Solu on

I Try a power func on F(x) = axr

I Then F′(x) = arxr−1, so we want arxr−1 = x3.

I r− 1 = 3 =⇒ r = 4

, and ar = 1 =⇒ a =14.

I So F(x) =14x4 is an an deriva ve.

I Check:ddx

(14x4)

= 4 · 14x4−1 = x3"

I Any others?

Yes, F(x) =14x4 + C is the most general form.

Page 20: Lesson 23: Antiderivatives (slides)

Antiderivatives of power functionsExample

Find an an deriva ve for the func on f(x) = x3.

Solu on

I Try a power func on F(x) = axr

I Then F′(x) = arxr−1, so we want arxr−1 = x3.

I r− 1 = 3 =⇒ r = 4, and ar = 1 =⇒ a =14.

I So F(x) =14x4 is an an deriva ve.

I Check:ddx

(14x4)

= 4 · 14x4−1 = x3"

I Any others?

Yes, F(x) =14x4 + C is the most general form.

Page 21: Lesson 23: Antiderivatives (slides)

Antiderivatives of power functionsExample

Find an an deriva ve for the func on f(x) = x3.

Solu on

I Try a power func on F(x) = axr

I Then F′(x) = arxr−1, so we want arxr−1 = x3.

I r− 1 = 3 =⇒ r = 4, and ar = 1 =⇒ a =14.

I So F(x) =14x4 is an an deriva ve.

I Check:ddx

(14x4)

= 4 · 14x4−1 = x3"

I Any others?

Yes, F(x) =14x4 + C is the most general form.

Page 22: Lesson 23: Antiderivatives (slides)

Antiderivatives of power functionsExample

Find an an deriva ve for the func on f(x) = x3.

Solu on

I Try a power func on F(x) = axr

I Then F′(x) = arxr−1, so we want arxr−1 = x3.

I r− 1 = 3 =⇒ r = 4, and ar = 1 =⇒ a =14.

I So F(x) =14x4 is an an deriva ve.

I Check:ddx

(14x4)

= 4 · 14x4−1 = x3"

I Any others?

Yes, F(x) =14x4 + C is the most general form.

Page 23: Lesson 23: Antiderivatives (slides)

Antiderivatives of power functionsExample

Find an an deriva ve for the func on f(x) = x3.

Solu on

I So F(x) =14x4 is an an deriva ve.

I Check:ddx

(14x4)

= 4 · 14x4−1 = x3"

I Any others?

Yes, F(x) =14x4 + C is the most general form.

Page 24: Lesson 23: Antiderivatives (slides)

Antiderivatives of power functionsExample

Find an an deriva ve for the func on f(x) = x3.

Solu on

I So F(x) =14x4 is an an deriva ve.

I Check:ddx

(14x4)

= 4 · 14x4−1 = x3"

I Any others?

Yes, F(x) =14x4 + C is the most general form.

Page 25: Lesson 23: Antiderivatives (slides)

Antiderivatives of power functionsExample

Find an an deriva ve for the func on f(x) = x3.

Solu on

I So F(x) =14x4 is an an deriva ve.

I Check:ddx

(14x4)

= 4 · 14x4−1 = x3"

I Any others?

Yes, F(x) =14x4 + C is the most general form.

Page 26: Lesson 23: Antiderivatives (slides)

Antiderivatives of power functionsExample

Find an an deriva ve for the func on f(x) = x3.

Solu on

I So F(x) =14x4 is an an deriva ve.

I Check:ddx

(14x4)

= 4 · 14x4−1 = x3"

I Any others? Yes, F(x) =14x4 + C is the most general form.

Page 27: Lesson 23: Antiderivatives (slides)

General power functionsFact (The Power Rule for an deriva ves)

If f(x) = xr, then

F(x) =1

r+ 1xr+1

is an an deriva ve for f…

as long as r ̸= −1.

Fact

If f(x) = x−1 =1x, then F(x) = ln |x|+ C is an an deriva ve for f.

Page 28: Lesson 23: Antiderivatives (slides)

General power functionsFact (The Power Rule for an deriva ves)

If f(x) = xr, then

F(x) =1

r+ 1xr+1

is an an deriva ve for f as long as r ̸= −1.

Fact

If f(x) = x−1 =1x, then F(x) = ln |x|+ C is an an deriva ve for f.

Page 29: Lesson 23: Antiderivatives (slides)

General power functionsFact (The Power Rule for an deriva ves)

If f(x) = xr, then

F(x) =1

r+ 1xr+1

is an an deriva ve for f as long as r ̸= −1.

Fact

If f(x) = x−1 =1x, then F(x) = ln |x|+ C is an an deriva ve for f.

Page 30: Lesson 23: Antiderivatives (slides)

What’s with the absolute value?

F(x) = ln |x| =

{ln(x) if x > 0;ln(−x) if x < 0.

I The domain of F is all nonzero numbers, while ln x is onlydefined on posi ve numbers.

I If x > 0,ddx

ln |x| = ddx

ln(x) =1x"

I If x < 0,ddx

ln |x| = ddx

ln(−x) =1−x

· (−1) =1x"

I We prefer the an deriva ve with the larger domain.

Page 31: Lesson 23: Antiderivatives (slides)

What’s with the absolute value?

F(x) = ln |x| =

{ln(x) if x > 0;ln(−x) if x < 0.

I The domain of F is all nonzero numbers, while ln x is onlydefined on posi ve numbers.

I If x > 0,ddx

ln |x|

=ddx

ln(x) =1x"

I If x < 0,ddx

ln |x| = ddx

ln(−x) =1−x

· (−1) =1x"

I We prefer the an deriva ve with the larger domain.

Page 32: Lesson 23: Antiderivatives (slides)

What’s with the absolute value?

F(x) = ln |x| =

{ln(x) if x > 0;ln(−x) if x < 0.

I The domain of F is all nonzero numbers, while ln x is onlydefined on posi ve numbers.

I If x > 0,ddx

ln |x| = ddx

ln(x)

=1x"

I If x < 0,ddx

ln |x| = ddx

ln(−x) =1−x

· (−1) =1x"

I We prefer the an deriva ve with the larger domain.

Page 33: Lesson 23: Antiderivatives (slides)

What’s with the absolute value?

F(x) = ln |x| =

{ln(x) if x > 0;ln(−x) if x < 0.

I The domain of F is all nonzero numbers, while ln x is onlydefined on posi ve numbers.

I If x > 0,ddx

ln |x| = ddx

ln(x) =1x

"

I If x < 0,ddx

ln |x| = ddx

ln(−x) =1−x

· (−1) =1x"

I We prefer the an deriva ve with the larger domain.

Page 34: Lesson 23: Antiderivatives (slides)

What’s with the absolute value?

F(x) = ln |x| =

{ln(x) if x > 0;ln(−x) if x < 0.

I The domain of F is all nonzero numbers, while ln x is onlydefined on posi ve numbers.

I If x > 0,ddx

ln |x| = ddx

ln(x) =1x"

I If x < 0,ddx

ln |x| = ddx

ln(−x) =1−x

· (−1) =1x"

I We prefer the an deriva ve with the larger domain.

Page 35: Lesson 23: Antiderivatives (slides)

What’s with the absolute value?

F(x) = ln |x| =

{ln(x) if x > 0;ln(−x) if x < 0.

I The domain of F is all nonzero numbers, while ln x is onlydefined on posi ve numbers.

I If x > 0,ddx

ln |x| = ddx

ln(x) =1x"

I If x < 0,ddx

ln |x|

=ddx

ln(−x) =1−x

· (−1) =1x"

I We prefer the an deriva ve with the larger domain.

Page 36: Lesson 23: Antiderivatives (slides)

What’s with the absolute value?

F(x) = ln |x| =

{ln(x) if x > 0;ln(−x) if x < 0.

I The domain of F is all nonzero numbers, while ln x is onlydefined on posi ve numbers.

I If x > 0,ddx

ln |x| = ddx

ln(x) =1x"

I If x < 0,ddx

ln |x| = ddx

ln(−x)

=1−x

· (−1) =1x"

I We prefer the an deriva ve with the larger domain.

Page 37: Lesson 23: Antiderivatives (slides)

What’s with the absolute value?

F(x) = ln |x| =

{ln(x) if x > 0;ln(−x) if x < 0.

I The domain of F is all nonzero numbers, while ln x is onlydefined on posi ve numbers.

I If x > 0,ddx

ln |x| = ddx

ln(x) =1x"

I If x < 0,ddx

ln |x| = ddx

ln(−x) =1−x

· (−1)

=1x"

I We prefer the an deriva ve with the larger domain.

Page 38: Lesson 23: Antiderivatives (slides)

What’s with the absolute value?

F(x) = ln |x| =

{ln(x) if x > 0;ln(−x) if x < 0.

I The domain of F is all nonzero numbers, while ln x is onlydefined on posi ve numbers.

I If x > 0,ddx

ln |x| = ddx

ln(x) =1x"

I If x < 0,ddx

ln |x| = ddx

ln(−x) =1−x

· (−1) =1x

"

I We prefer the an deriva ve with the larger domain.

Page 39: Lesson 23: Antiderivatives (slides)

What’s with the absolute value?

F(x) = ln |x| =

{ln(x) if x > 0;ln(−x) if x < 0.

I The domain of F is all nonzero numbers, while ln x is onlydefined on posi ve numbers.

I If x > 0,ddx

ln |x| = ddx

ln(x) =1x"

I If x < 0,ddx

ln |x| = ddx

ln(−x) =1−x

· (−1) =1x"

I We prefer the an deriva ve with the larger domain.

Page 40: Lesson 23: Antiderivatives (slides)

What’s with the absolute value?

F(x) = ln |x| =

{ln(x) if x > 0;ln(−x) if x < 0.

I The domain of F is all nonzero numbers, while ln x is onlydefined on posi ve numbers.

I If x > 0,ddx

ln |x| = ddx

ln(x) =1x"

I If x < 0,ddx

ln |x| = ddx

ln(−x) =1−x

· (−1) =1x"

I We prefer the an deriva ve with the larger domain.

Page 41: Lesson 23: Antiderivatives (slides)

Graph of ln |x|

.. x.

y

. f(x) = 1/x

Page 42: Lesson 23: Antiderivatives (slides)

Graph of ln |x|

.. x.

y

. f(x) = 1/x.

F(x) = ln(x)

Page 43: Lesson 23: Antiderivatives (slides)

Graph of ln |x|

.. x.

y

. f(x) = 1/x.

F(x) = ln |x|

Page 44: Lesson 23: Antiderivatives (slides)

Combinations of antiderivatives

Fact (Sum and Constant Mul ple Rule for An deriva ves)

I If F is an an deriva ve of f and G is an an deriva ve of g, thenF+ G is an an deriva ve of f+ g.

I If F is an an deriva ve of f and c is a constant, then cF is anan deriva ve of cf.

Page 45: Lesson 23: Antiderivatives (slides)

Combinations of antiderivativesProof.These follow from the sum and constant mul ple rule forderiva ves:

I If F′ = f and G′ = g, then

(F+ G)′ = F′ + G′ = f+ g

I Or, if F′ = f,(cF)′ = cF′ = cf

Page 46: Lesson 23: Antiderivatives (slides)

Antiderivatives of PolynomialsExample

Find an an deriva ve for f(x) = 16x+ 5.

Solu on

The expression12x2 is an an deriva ve for x, and x is an

an deriva ve for 1. So

F(x) = 16 ·(12x2)+ 5 · x+ C = 8x2 + 5x+ C

is the an deriva ve of f.

Page 47: Lesson 23: Antiderivatives (slides)

Antiderivatives of PolynomialsExample

Find an an deriva ve for f(x) = 16x+ 5.

Solu on

The expression12x2 is an an deriva ve for x, and x is an

an deriva ve for 1. So

F(x) = 16 ·(12x2)+ 5 · x+ C = 8x2 + 5x+ C

is the an deriva ve of f.

Page 48: Lesson 23: Antiderivatives (slides)

Antiderivatives of Polynomials

Ques on

Do we need two C’s or just one?

AnswerJust one. A combina on of two arbitrary constants is s ll anarbitrary constant.

Page 49: Lesson 23: Antiderivatives (slides)

Antiderivatives of Polynomials

Ques on

Do we need two C’s or just one?

AnswerJust one. A combina on of two arbitrary constants is s ll anarbitrary constant.

Page 50: Lesson 23: Antiderivatives (slides)

Exponential FunctionsFactIf f(x) = ax, f′(x) = (ln a)ax.

Accordingly,Fact

If f(x) = ax, then F(x) =1ln a

ax + C is the an deriva ve of f.

Proof.Check it yourself.

In par cular,FactIf f(x) = ex, then F(x) = ex + C is the an deriva ve of f.

Page 51: Lesson 23: Antiderivatives (slides)

Exponential FunctionsFactIf f(x) = ax, f′(x) = (ln a)ax.

Accordingly,Fact

If f(x) = ax, then F(x) =1ln a

ax + C is the an deriva ve of f.

Proof.Check it yourself.

In par cular,FactIf f(x) = ex, then F(x) = ex + C is the an deriva ve of f.

Page 52: Lesson 23: Antiderivatives (slides)

Exponential FunctionsFactIf f(x) = ax, f′(x) = (ln a)ax.

Accordingly,Fact

If f(x) = ax, then F(x) =1ln a

ax + C is the an deriva ve of f.

Proof.Check it yourself.

In par cular,FactIf f(x) = ex, then F(x) = ex + C is the an deriva ve of f.

Page 53: Lesson 23: Antiderivatives (slides)

Exponential Functions

In par cular,

FactIf f(x) = ex, then F(x) = ex + C is the an deriva ve of f.

Page 54: Lesson 23: Antiderivatives (slides)

Exponential Functions

In par cular,

FactIf f(x) = ex, then F(x) = ex + C is the an deriva ve of f.

Page 55: Lesson 23: Antiderivatives (slides)

Logarithmic functions?I Remember we found F(x) = x ln x− x is an an deriva ve off(x) = ln x.

I This is not obvious. See Calc II for the full story.I However, using the fact that loga x =

ln xln a

, we get:

FactIf f(x) = loga(x)

F(x) =1ln a

(x ln x− x) + C = x loga x−1ln a

x+ C

is the an deriva ve of f(x).

Page 56: Lesson 23: Antiderivatives (slides)

Logarithmic functions?I Remember we found F(x) = x ln x− x is an an deriva ve off(x) = ln x.

I This is not obvious. See Calc II for the full story.

I However, using the fact that loga x =ln xln a

, we get:

FactIf f(x) = loga(x)

F(x) =1ln a

(x ln x− x) + C = x loga x−1ln a

x+ C

is the an deriva ve of f(x).

Page 57: Lesson 23: Antiderivatives (slides)

Logarithmic functions?I Remember we found F(x) = x ln x− x is an an deriva ve off(x) = ln x.

I This is not obvious. See Calc II for the full story.I However, using the fact that loga x =

ln xln a

, we get:

FactIf f(x) = loga(x)

F(x) =1ln a

(x ln x− x) + C = x loga x−1ln a

x+ C

is the an deriva ve of f(x).

Page 58: Lesson 23: Antiderivatives (slides)

Trigonometric functionsFact

ddx

sin x = cos xddx

cos x = − sin x

So to turn these around,Fact

I The func on F(x) = − cos x+ C is the an deriva ve off(x) = sin x.

I The func on F(x) = sin x+ C is the an deriva ve off(x) = cos x.

Page 59: Lesson 23: Antiderivatives (slides)

Trigonometric functionsFact

ddx

sin x = cos xddx

cos x = − sin x

So to turn these around,Fact

I The func on F(x) = − cos x+ C is the an deriva ve off(x) = sin x.

I The func on F(x) = sin x+ C is the an deriva ve off(x) = cos x.

Page 60: Lesson 23: Antiderivatives (slides)

Trigonometric functionsFact

ddx

sin x = cos xddx

cos x = − sin x

So to turn these around,Fact

I The func on F(x) = − cos x+ C is the an deriva ve off(x) = sin x.

I The func on F(x) = sin x+ C is the an deriva ve off(x) = cos x.

Page 61: Lesson 23: Antiderivatives (slides)

More TrigExample

Find an an deriva ve of f(x) = tan x.

AnswerF(x) = ln | sec x|.

Check

ddx

=1

sec x· ddx

sec x

=1

sec x· sec x tan x = tan x"

More about this later.

Page 62: Lesson 23: Antiderivatives (slides)

More TrigExample

Find an an deriva ve of f(x) = tan x.

Solu on???

AnswerF(x) = ln | sec x|.

Check

ddx

=1

sec x· ddx

sec x

=1

sec x· sec x tan x = tan x"

More about this later.

Page 63: Lesson 23: Antiderivatives (slides)

More TrigExample

Find an an deriva ve of f(x) = tan x.

AnswerF(x) = ln | sec x|.

Check

ddx

=1

sec x· ddx

sec x

=1

sec x· sec x tan x = tan x"

More about this later.

Page 64: Lesson 23: Antiderivatives (slides)

More TrigExample

Find an an deriva ve of f(x) = tan x.

AnswerF(x) = ln | sec x|.

Check

ddx

=1

sec x· ddx

sec x

=1

sec x· sec x tan x = tan x"

More about this later.

Page 65: Lesson 23: Antiderivatives (slides)

More TrigExample

Find an an deriva ve of f(x) = tan x.

AnswerF(x) = ln | sec x|.

Check

ddx

=1

sec x· ddx

sec x

=1

sec x· sec x tan x = tan x"

More about this later.

Page 66: Lesson 23: Antiderivatives (slides)

More TrigExample

Find an an deriva ve of f(x) = tan x.

AnswerF(x) = ln | sec x|.

Check

ddx

=1

sec x· ddx

sec x =1

sec x· sec x tan x

= tan x"

More about this later.

Page 67: Lesson 23: Antiderivatives (slides)

More TrigExample

Find an an deriva ve of f(x) = tan x.

AnswerF(x) = ln | sec x|.

Check

ddx

=1

sec x· ddx

sec x =1

sec x· sec x tan x = tan x

"

More about this later.

Page 68: Lesson 23: Antiderivatives (slides)

More TrigExample

Find an an deriva ve of f(x) = tan x.

AnswerF(x) = ln | sec x|.

Check

ddx

=1

sec x· ddx

sec x =1

sec x· sec x tan x = tan x"

More about this later.

Page 69: Lesson 23: Antiderivatives (slides)

More TrigExample

Find an an deriva ve of f(x) = tan x.

AnswerF(x) = ln | sec x|.

Check

ddx

=1

sec x· ddx

sec x =1

sec x· sec x tan x = tan x"

More about this later.

Page 70: Lesson 23: Antiderivatives (slides)

Antiderivatives of piecewise functions

Example

Let

f(x) =

{x if 0 ≤ x ≤ 1;1− x2 if 1 < x.

Find the an deriva ve of f with F(0) = 1.

Page 71: Lesson 23: Antiderivatives (slides)

Antiderivatives of piecewise functions

Solu onWe can an differen ate each piece:

F(x) =

12x2 + C1 if 0 ≤ x ≤ 1;

x− 13x3 + C2 if 1 < x.

The constants need to be chosen so that F(0) = 1 and F iscon nuous (at 1).

Page 72: Lesson 23: Antiderivatives (slides)

F(x) =

12x2 + C1 if 0 ≤ x ≤ 1;

x− 13x3 + C2 if 1 < x.

I Note F(0) =1202 + C1 = C1, so if F(0) is to be 1, C1 = 1.

I This means limx→1−

F(x) =1212 + 1 =

32.

I On the other hand,

limx→1+

F(x) = 1− 13+ C2 =

23+ C2

So for F to be con nuous we need32=

23+ C2. Solving, C2 =

56.

Page 73: Lesson 23: Antiderivatives (slides)

F(x) =

12x2 + C1 if 0 ≤ x ≤ 1;

x− 13x3 + C2 if 1 < x.

I Note F(0) =1202 + C1 = C1, so if F(0) is to be 1, C1 = 1.

I This means limx→1−

F(x) =1212 + 1 =

32.

I On the other hand,

limx→1+

F(x) = 1− 13+ C2 =

23+ C2

So for F to be con nuous we need32=

23+ C2. Solving, C2 =

56.

Page 74: Lesson 23: Antiderivatives (slides)

F(x) =

12x2 + C1 if 0 ≤ x ≤ 1;

x− 13x3 + C2 if 1 < x.

I Note F(0) =1202 + C1 = C1, so if F(0) is to be 1, C1 = 1.

I This means limx→1−

F(x) =1212 + 1 =

32.

I On the other hand,

limx→1+

F(x) = 1− 13+ C2 =

23+ C2

So for F to be con nuous we need32=

23+ C2. Solving, C2 =

56.

Page 75: Lesson 23: Antiderivatives (slides)

OutlineWhat is an an deriva ve?

Tabula ng An deriva vesPower func onsCombina onsExponen al func onsTrigonometric func onsAn deriva ves of piecewise func ons

Finding An deriva ves Graphically

Rec linear mo on

Page 76: Lesson 23: Antiderivatives (slides)

Finding Antiderivatives Graphically

ProblemPictured is the graph of afunc on f. Draw the graph ofan an deriva ve for f.

..x

.

y

..1

..2

..3

..4

..5

..6

.......y = f(x)

Page 77: Lesson 23: Antiderivatives (slides)

Using f to make a sign chart for FAssuming F′ = f, we can make a sign chart for f and f′ to find theintervals of monotonicity and concavity for F:

..x

.

y

..1

..2

..3

..4

..5

..6

......

.. f = F′.F

..1

..2

..3

..4

..5

..6

. +. +. −. −. +.↗

.↗

.↘

.↘

.↗

.

max

.

min

.

f′ = F′′

.

F

..

1

..

2

..

3

..

4

..

5

..

6

.

++

.

−−

.

−−

.

++

.

++

.

.

.

.

.

.

IP

.

IP

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

"

.

.

.

"

.

?

.

?

.

?

.

?

.

?

.

?

The only ques on le is: What are the func on values?

Page 78: Lesson 23: Antiderivatives (slides)

Using f to make a sign chart for FAssuming F′ = f, we can make a sign chart for f and f′ to find theintervals of monotonicity and concavity for F:

..x

.

y

..1

..2

..3

..4

..5

..6

......

.. f = F′.F

..1

..2

..3

..4

..5

..6

. +

. +. −. −. +.↗

.↗

.↘

.↘

.↗

.

max

.

min

.

f′ = F′′

.

F

..

1

..

2

..

3

..

4

..

5

..

6

.

++

.

−−

.

−−

.

++

.

++

.

.

.

.

.

.

IP

.

IP

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

"

.

.

.

"

.

?

.

?

.

?

.

?

.

?

.

?

The only ques on le is: What are the func on values?

Page 79: Lesson 23: Antiderivatives (slides)

Using f to make a sign chart for FAssuming F′ = f, we can make a sign chart for f and f′ to find theintervals of monotonicity and concavity for F:

..x

.

y

..1

..2

..3

..4

..5

..6

......

.. f = F′.F

..1

..2

..3

..4

..5

..6

. +. +

. −. −. +.↗

.↗

.↘

.↘

.↗

.

max

.

min

.

f′ = F′′

.

F

..

1

..

2

..

3

..

4

..

5

..

6

.

++

.

−−

.

−−

.

++

.

++

.

.

.

.

.

.

IP

.

IP

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

"

.

.

.

"

.

?

.

?

.

?

.

?

.

?

.

?

The only ques on le is: What are the func on values?

Page 80: Lesson 23: Antiderivatives (slides)

Using f to make a sign chart for FAssuming F′ = f, we can make a sign chart for f and f′ to find theintervals of monotonicity and concavity for F:

..x

.

y

..1

..2

..3

..4

..5

..6

......

.. f = F′.F

..1

..2

..3

..4

..5

..6

. +. +. −

. −. +.↗

.↗

.↘

.↘

.↗

.

max

.

min

.

f′ = F′′

.

F

..

1

..

2

..

3

..

4

..

5

..

6

.

++

.

−−

.

−−

.

++

.

++

.

.

.

.

.

.

IP

.

IP

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

"

.

.

.

"

.

?

.

?

.

?

.

?

.

?

.

?

The only ques on le is: What are the func on values?

Page 81: Lesson 23: Antiderivatives (slides)

Using f to make a sign chart for FAssuming F′ = f, we can make a sign chart for f and f′ to find theintervals of monotonicity and concavity for F:

..x

.

y

..1

..2

..3

..4

..5

..6

......

.. f = F′.F

..1

..2

..3

..4

..5

..6

. +. +. −. −

. +.↗

.↗

.↘

.↘

.↗

.

max

.

min

.

f′ = F′′

.

F

..

1

..

2

..

3

..

4

..

5

..

6

.

++

.

−−

.

−−

.

++

.

++

.

.

.

.

.

.

IP

.

IP

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

"

.

.

.

"

.

?

.

?

.

?

.

?

.

?

.

?

The only ques on le is: What are the func on values?

Page 82: Lesson 23: Antiderivatives (slides)

Using f to make a sign chart for FAssuming F′ = f, we can make a sign chart for f and f′ to find theintervals of monotonicity and concavity for F:

..x

.

y

..1

..2

..3

..4

..5

..6

......

.. f = F′.F

..1

..2

..3

..4

..5

..6

. +. +. −. −. +

.↗

.↗

.↘

.↘

.↗

.

max

.

min

.

f′ = F′′

.

F

..

1

..

2

..

3

..

4

..

5

..

6

.

++

.

−−

.

−−

.

++

.

++

.

.

.

.

.

.

IP

.

IP

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

"

.

.

.

"

.

?

.

?

.

?

.

?

.

?

.

?

The only ques on le is: What are the func on values?

Page 83: Lesson 23: Antiderivatives (slides)

Using f to make a sign chart for FAssuming F′ = f, we can make a sign chart for f and f′ to find theintervals of monotonicity and concavity for F:

..x

.

y

..1

..2

..3

..4

..5

..6

......

.. f = F′.F

..1

..2

..3

..4

..5

..6

. +. +. −. −. +.↗

.↗

.↘

.↘

.↗

.

max

.

min

.

f′ = F′′

.

F

..

1

..

2

..

3

..

4

..

5

..

6

.

++

.

−−

.

−−

.

++

.

++

.

.

.

.

.

.

IP

.

IP

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

"

.

.

.

"

.

?

.

?

.

?

.

?

.

?

.

?

The only ques on le is: What are the func on values?

Page 84: Lesson 23: Antiderivatives (slides)

Using f to make a sign chart for FAssuming F′ = f, we can make a sign chart for f and f′ to find theintervals of monotonicity and concavity for F:

..x

.

y

..1

..2

..3

..4

..5

..6

......

.. f = F′.F

..1

..2

..3

..4

..5

..6

. +. +. −. −. +.↗

.↗

.↘

.↘

.↗

.

max

.

min

.

f′ = F′′

.

F

..

1

..

2

..

3

..

4

..

5

..

6

.

++

.

−−

.

−−

.

++

.

++

.

.

.

.

.

.

IP

.

IP

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

"

.

.

.

"

.

?

.

?

.

?

.

?

.

?

.

?

The only ques on le is: What are the func on values?

Page 85: Lesson 23: Antiderivatives (slides)

Using f to make a sign chart for FAssuming F′ = f, we can make a sign chart for f and f′ to find theintervals of monotonicity and concavity for F:

..x

.

y

..1

..2

..3

..4

..5

..6

......

.. f = F′.F

..1

..2

..3

..4

..5

..6

. +. +. −. −. +.↗

.↗

.↘

.↘

.↗

.

max

.

min

.

f′ = F′′

.

F

..

1

..

2

..

3

..

4

..

5

..

6

.

++

.

−−

.

−−

.

++

.

++

.

.

.

.

.

.

IP

.

IP

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

"

.

.

.

"

.

?

.

?

.

?

.

?

.

?

.

?

The only ques on le is: What are the func on values?

Page 86: Lesson 23: Antiderivatives (slides)

Using f to make a sign chart for FAssuming F′ = f, we can make a sign chart for f and f′ to find theintervals of monotonicity and concavity for F:

..x

.

y

..1

..2

..3

..4

..5

..6

......

.. f = F′.F

..1

..2

..3

..4

..5

..6

. +. +. −. −. +.↗

.↗

.↘

.↘

.↗

.

max

.

min

.

f′ = F′′

.

F

..

1

..

2

..

3

..

4

..

5

..

6

.

++

.

−−

.

−−

.

++

.

++

.

.

.

.

.

.

IP

.

IP

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

"

.

.

.

"

.

?

.

?

.

?

.

?

.

?

.

?

The only ques on le is: What are the func on values?

Page 87: Lesson 23: Antiderivatives (slides)

Using f to make a sign chart for FAssuming F′ = f, we can make a sign chart for f and f′ to find theintervals of monotonicity and concavity for F:

..x

.

y

..1

..2

..3

..4

..5

..6

......

.. f = F′.F

..1

..2

..3

..4

..5

..6

. +. +. −. −. +.↗

.↗

.↘

.↘

.↗

.

max

.

min

.

f′ = F′′

.

F

..

1

..

2

..

3

..

4

..

5

..

6

.

++

.

−−

.

−−

.

++

.

++

.

.

.

.

.

.

IP

.

IP

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

"

.

.

.

"

.

?

.

?

.

?

.

?

.

?

.

?

The only ques on le is: What are the func on values?

Page 88: Lesson 23: Antiderivatives (slides)

Using f to make a sign chart for FAssuming F′ = f, we can make a sign chart for f and f′ to find theintervals of monotonicity and concavity for F:

..x

.

y

..1

..2

..3

..4

..5

..6

......

.. f = F′.F

..1

..2

..3

..4

..5

..6

. +. +. −. −. +.↗

.↗

.↘

.↘

.↗

.

max

.

min

.

f′ = F′′

.

F

..

1

..

2

..

3

..

4

..

5

..

6

.

++

.

−−

.

−−

.

++

.

++

.

.

.

.

.

.

IP

.

IP

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

"

.

.

.

"

.

?

.

?

.

?

.

?

.

?

.

?

The only ques on le is: What are the func on values?

Page 89: Lesson 23: Antiderivatives (slides)

Using f to make a sign chart for FAssuming F′ = f, we can make a sign chart for f and f′ to find theintervals of monotonicity and concavity for F:

..x

.

y

..1

..2

..3

..4

..5

..6

......

.. f = F′.F

..1

..2

..3

..4

..5

..6

. +. +. −. −. +.↗

.↗

.↘

.↘

.↗

.

max

.

min

.

f′ = F′′

.

F

..

1

..

2

..

3

..

4

..

5

..

6

.

++

.

−−

.

−−

.

++

.

++

.

.

.

.

.

.

IP

.

IP

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

"

.

.

.

"

.

?

.

?

.

?

.

?

.

?

.

?

The only ques on le is: What are the func on values?

Page 90: Lesson 23: Antiderivatives (slides)

Using f to make a sign chart for FAssuming F′ = f, we can make a sign chart for f and f′ to find theintervals of monotonicity and concavity for F:

..x

.

y

..1

..2

..3

..4

..5

..6

......

.. f = F′.F

..1

..2

..3

..4

..5

..6

. +. +. −. −. +.↗

.↗

.↘

.↘

.↗

.

max

.

min

.

f′ = F′′

.

F

..

1

..

2

..

3

..

4

..

5

..

6

.

++

.

−−

.

−−

.

++

.

++

.

.

.

.

.

.

IP

.

IP

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

"

.

.

.

"

.

?

.

?

.

?

.

?

.

?

.

?

The only ques on le is: What are the func on values?

Page 91: Lesson 23: Antiderivatives (slides)

Using f to make a sign chart for FAssuming F′ = f, we can make a sign chart for f and f′ to find theintervals of monotonicity and concavity for F:

..x

.

y

..1

..2

..3

..4

..5

..6

......

.. f = F′.F

..1

..2

..3

..4

..5

..6

. +. +. −. −. +.↗

.↗

.↘

.↘

.↗

.

max

.

min

.

f′ = F′′

.

F

..

1

..

2

..

3

..

4

..

5

..

6

.

++

.

−−

.

−−

.

++

.

++

.

.

.

.

.

.

IP

.

IP

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

"

.

.

.

"

.

?

.

?

.

?

.

?

.

?

.

?

The only ques on le is: What are the func on values?

Page 92: Lesson 23: Antiderivatives (slides)

Using f to make a sign chart for FAssuming F′ = f, we can make a sign chart for f and f′ to find theintervals of monotonicity and concavity for F:

..x

.

y

..1

..2

..3

..4

..5

..6

......

.. f = F′.F

..1

..2

..3

..4

..5

..6

. +. +. −. −. +.↗

.↗

.↘

.↘

.↗

.

max

.

min

.

f′ = F′′

.

F

..

1

..

2

..

3

..

4

..

5

..

6

.

++

.

−−

.

−−

.

++

.

++

.

.

.

.

.

.

IP

.

IP

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

"

.

.

.

"

.

?

.

?

.

?

.

?

.

?

.

?

The only ques on le is: What are the func on values?

Page 93: Lesson 23: Antiderivatives (slides)

Using f to make a sign chart for FAssuming F′ = f, we can make a sign chart for f and f′ to find theintervals of monotonicity and concavity for F:

..x

.

y

..1

..2

..3

..4

..5

..6

......

.. f = F′.F

..1

..2

..3

..4

..5

..6

. +. +. −. −. +.↗

.↗

.↘

.↘

.↗

.

max

.

min

.

f′ = F′′

.

F

..

1

..

2

..

3

..

4

..

5

..

6

.

++

.

−−

.

−−

.

++

.

++

.

.

.

.

.

.

IP

.

IP

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

"

.

.

.

"

.

?

.

?

.

?

.

?

.

?

.

?

The only ques on le is: What are the func on values?

Page 94: Lesson 23: Antiderivatives (slides)

Using f to make a sign chart for FAssuming F′ = f, we can make a sign chart for f and f′ to find theintervals of monotonicity and concavity for F:

..x

.

y

..1

..2

..3

..4

..5

..6

......

.. f = F′.F

..1

..2

..3

..4

..5

..6

. +. +. −. −. +.↗

.↗

.↘

.↘

.↗

.

max

.

min

.

f′ = F′′

.

F

..

1

..

2

..

3

..

4

..

5

..

6

.

++

.

−−

.

−−

.

++

.

++

.

.

.

.

.

.

IP

.

IP

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

"

.

.

.

"

.

?

.

?

.

?

.

?

.

?

.

?

The only ques on le is: What are the func on values?

Page 95: Lesson 23: Antiderivatives (slides)

Using f to make a sign chart for FAssuming F′ = f, we can make a sign chart for f and f′ to find theintervals of monotonicity and concavity for F:

..x

.

y

..1

..2

..3

..4

..5

..6

......

.. f = F′.F

..1

..2

..3

..4

..5

..6

. +. +. −. −. +.↗

.↗

.↘

.↘

.↗

.

max

.

min

.

f′ = F′′

.

F

..

1

..

2

..

3

..

4

..

5

..

6

.

++

.

−−

.

−−

.

++

.

++

.

.

.

.

.

.

IP

.

IP

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

"

.

.

.

"

.

?

.

?

.

?

.

?

.

?

.

?

The only ques on le is: What are the func on values?

Page 96: Lesson 23: Antiderivatives (slides)

Using f to make a sign chart for FAssuming F′ = f, we can make a sign chart for f and f′ to find theintervals of monotonicity and concavity for F:

..x

.

y

..1

..2

..3

..4

..5

..6

......

.. f = F′.F

..1

..2

..3

..4

..5

..6

. +. +. −. −. +.↗

.↗

.↘

.↘

.↗

.

max

.

min

.

f′ = F′′

.

F

..

1

..

2

..

3

..

4

..

5

..

6

.

++

.

−−

.

−−

.

++

.

++

.

.

.

.

.

.

IP

.

IP

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

"

.

.

.

"

.

?

.

?

.

?

.

?

.

?

.

?

The only ques on le is: What are the func on values?

Page 97: Lesson 23: Antiderivatives (slides)

Using f to make a sign chart for FAssuming F′ = f, we can make a sign chart for f and f′ to find theintervals of monotonicity and concavity for F:

..x

.

y

..1

..2

..3

..4

..5

..6

......

.. f = F′.F

..1

..2

..3

..4

..5

..6

. +. +. −. −. +.↗

.↗

.↘

.↘

.↗

.

max

.

min

.

f′ = F′′

.

F

..

1

..

2

..

3

..

4

..

5

..

6

.

++

.

−−

.

−−

.

++

.

++

.

.

.

.

.

.

IP

.

IP

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

"

.

.

.

"

.

?

.

?

.

?

.

?

.

?

.

?

The only ques on le is: What are the func on values?

Page 98: Lesson 23: Antiderivatives (slides)

Using f to make a sign chart for FAssuming F′ = f, we can make a sign chart for f and f′ to find theintervals of monotonicity and concavity for F:

..x

.

y

..1

..2

..3

..4

..5

..6

......

.. f = F′.F

..1

..2

..3

..4

..5

..6

. +. +. −. −. +.↗

.↗

.↘

.↘

.↗

.

max

.

min

.

f′ = F′′

.

F

..

1

..

2

..

3

..

4

..

5

..

6

.

++

.

−−

.

−−

.

++

.

++

.

.

.

.

.

.

IP

.

IP

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

"

.

.

.

"

.

?

.

?

.

?

.

?

.

?

.

?

The only ques on le is: What are the func on values?

Page 99: Lesson 23: Antiderivatives (slides)

Using f to make a sign chart for FAssuming F′ = f, we can make a sign chart for f and f′ to find theintervals of monotonicity and concavity for F:

..x

.

y

..1

..2

..3

..4

..5

..6

......

.. f = F′.F

..1

..2

..3

..4

..5

..6

. +. +. −. −. +.↗

.↗

.↘

.↘

.↗

.

max

.

min

.

f′ = F′′

.

F

..

1

..

2

..

3

..

4

..

5

..

6

.

++

.

−−

.

−−

.

++

.

++

.

.

.

.

.

.

IP

.

IP

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

"

.

.

.

"

.

?

.

?

.

?

.

?

.

?

.

?

The only ques on le is: What are the func on values?

Page 100: Lesson 23: Antiderivatives (slides)

Using f to make a sign chart for FAssuming F′ = f, we can make a sign chart for f and f′ to find theintervals of monotonicity and concavity for F:

..x

.

y

..1

..2

..3

..4

..5

..6

......

.. f = F′.F

..1

..2

..3

..4

..5

..6

. +. +. −. −. +.↗

.↗

.↘

.↘

.↗

.

max

.

min

.

f′ = F′′

.

F

..

1

..

2

..

3

..

4

..

5

..

6

.

++

.

−−

.

−−

.

++

.

++

.

.

.

.

.

.

IP

.

IP

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

"

.

.

.

"

.

?

.

?

.

?

.

?

.

?

.

?

The only ques on le is: What are the func on values?

Page 101: Lesson 23: Antiderivatives (slides)

Using f to make a sign chart for FAssuming F′ = f, we can make a sign chart for f and f′ to find theintervals of monotonicity and concavity for F:

..x

.

y

..1

..2

..3

..4

..5

..6

......

.. f = F′.F

..1

..2

..3

..4

..5

..6

. +. +. −. −. +.↗

.↗

.↘

.↘

.↗

.

max

.

min

.

f′ = F′′

.

F

..

1

..

2

..

3

..

4

..

5

..

6

.

++

.

−−

.

−−

.

++

.

++

.

.

.

.

.

.

IP

.

IP

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

"

.

.

.

"

.

?

.

?

.

?

.

?

.

?

.

?

The only ques on le is: What are the func on values?

Page 102: Lesson 23: Antiderivatives (slides)

Using f to make a sign chart for FAssuming F′ = f, we can make a sign chart for f and f′ to find theintervals of monotonicity and concavity for F:

..x

.

y

..1

..2

..3

..4

..5

..6

......

.. f = F′.F

..1

..2

..3

..4

..5

..6

. +. +. −. −. +.↗

.↗

.↘

.↘

.↗

.

max

.

min

.

f′ = F′′

.

F

..

1

..

2

..

3

..

4

..

5

..

6

.

++

.

−−

.

−−

.

++

.

++

.

.

.

.

.

.

IP

.

IP

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

"

.

.

.

"

.

?

.

?

.

?

.

?

.

?

.

?

The only ques on le is: What are the func on values?

Page 103: Lesson 23: Antiderivatives (slides)

Using f to make a sign chart for FAssuming F′ = f, we can make a sign chart for f and f′ to find theintervals of monotonicity and concavity for F:

..x

.

y

..1

..2

..3

..4

..5

..6

......

.. f = F′.F

..1

..2

..3

..4

..5

..6

. +. +. −. −. +.↗

.↗

.↘

.↘

.↗

.

max

.

min

.

f′ = F′′

.

F

..

1

..

2

..

3

..

4

..

5

..

6

.

++

.

−−

.

−−

.

++

.

++

.

.

.

.

.

.

IP

.

IP

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

".

"

.

.

.

"

.

?

.

?

.

?

.

?

.

?

.

?

The only ques on le is: What are the func on values?

Page 104: Lesson 23: Antiderivatives (slides)

Using f to make a sign chart for FAssuming F′ = f, we can make a sign chart for f and f′ to find theintervals of monotonicity and concavity for F:

..x

.

y

..1

..2

..3

..4

..5

..6

......

.. f = F′.F

..1

..2

..3

..4

..5

..6

. +. +. −. −. +.↗

.↗

.↘

.↘

.↗

.

max

.

min

.

f′ = F′′

.

F

..

1

..

2

..

3

..

4

..

5

..

6

.

++

.

−−

.

−−

.

++

.

++

.

.

.

.

.

.

IP

.

IP

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

".

"

.

.

.

"

.

?

.

?

.

?

.

?

.

?

.

?

The only ques on le is: What are the func on values?

Page 105: Lesson 23: Antiderivatives (slides)

Using f to make a sign chart for FAssuming F′ = f, we can make a sign chart for f and f′ to find theintervals of monotonicity and concavity for F:

..x

.

y

..1

..2

..3

..4

..5

..6

......

.. f = F′.F

..1

..2

..3

..4

..5

..6

. +. +. −. −. +.↗

.↗

.↘

.↘

.↗

.

max

.

min

.

f′ = F′′

.

F

..

1

..

2

..

3

..

4

..

5

..

6

.

++

.

−−

.

−−

.

++

.

++

.

.

.

.

.

.

IP

.

IP

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

".

"

.

.

.

"

.

?

.

?

.

?

.

?

.

?

.

?

The only ques on le is: What are the func on values?

Page 106: Lesson 23: Antiderivatives (slides)

Using f to make a sign chart for FAssuming F′ = f, we can make a sign chart for f and f′ to find theintervals of monotonicity and concavity for F:

..x

.

y

..1

..2

..3

..4

..5

..6

......

.. f = F′.F

..1

..2

..3

..4

..5

..6

. +. +. −. −. +.↗

.↗

.↘

.↘

.↗

.

max

.

min

.

f′ = F′′

.

F

..

1

..

2

..

3

..

4

..

5

..

6

.

++

.

−−

.

−−

.

++

.

++

.

.

.

.

.

.

IP

.

IP

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

".

"

.

.

.

"

.

?

.

?

.

?

.

?

.

?

.

?

The only ques on le is: What are the func on values?

Page 107: Lesson 23: Antiderivatives (slides)

Using f to make a sign chart for FAssuming F′ = f, we can make a sign chart for f and f′ to find theintervals of monotonicity and concavity for F:

..x

.

y

..1

..2

..3

..4

..5

..6

......

.. f = F′.F

..1

..2

..3

..4

..5

..6

. +. +. −. −. +.↗

.↗

.↘

.↘

.↗

.

max

.

min

.

f′ = F′′

.

F

..

1

..

2

..

3

..

4

..

5

..

6

.

++

.

−−

.

−−

.

++

.

++

.

.

.

.

.

.

IP

.

IP

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

".

"

.

.

.

".

?

.

?

.

?

.

?

.

?

.

?

The only ques on le is: What are the func on values?

Page 108: Lesson 23: Antiderivatives (slides)

Could you repeat the question?ProblemBelow is the graph of a func on f. Draw the graph of thean deriva ve for f with F(1) = 0.

Solu on

I We start with F(1) = 0.I Using the sign chart, we draw arcswith the specified monotonicity andconcavity

I It’s harder to tell if/when F crossesthe axis; more about that later.

..x

.

y

..1

..2

..3

..4

..5

..6

.......f

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

".

.

.

"

.

IP

.

max

.

IP

.

min

......

Page 109: Lesson 23: Antiderivatives (slides)

Could you repeat the question?ProblemBelow is the graph of a func on f. Draw the graph of thean deriva ve for f with F(1) = 0.

Solu on

I We start with F(1) = 0.

I Using the sign chart, we draw arcswith the specified monotonicity andconcavity

I It’s harder to tell if/when F crossesthe axis; more about that later.

..x

.

y

..1

..2

..3

..4

..5

..6

.......f

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

".

.

.

"

.

IP

.

max

.

IP

.

min

.

.....

Page 110: Lesson 23: Antiderivatives (slides)

Could you repeat the question?ProblemBelow is the graph of a func on f. Draw the graph of thean deriva ve for f with F(1) = 0.

Solu on

I We start with F(1) = 0.I Using the sign chart, we draw arcswith the specified monotonicity andconcavity

I It’s harder to tell if/when F crossesthe axis; more about that later.

..x

.

y

..1

..2

..3

..4

..5

..6

.......f

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

".

.

.

"

.

IP

.

max

.

IP

.

min

.

.....

Page 111: Lesson 23: Antiderivatives (slides)

Could you repeat the question?ProblemBelow is the graph of a func on f. Draw the graph of thean deriva ve for f with F(1) = 0.

Solu on

I We start with F(1) = 0.I Using the sign chart, we draw arcswith the specified monotonicity andconcavity

I It’s harder to tell if/when F crossesthe axis; more about that later.

..x

.

y

..1

..2

..3

..4

..5

..6

.......f

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

".

.

.

"

.

IP

.

max

.

IP

.

min

..

....

Page 112: Lesson 23: Antiderivatives (slides)

Could you repeat the question?ProblemBelow is the graph of a func on f. Draw the graph of thean deriva ve for f with F(1) = 0.

Solu on

I We start with F(1) = 0.I Using the sign chart, we draw arcswith the specified monotonicity andconcavity

I It’s harder to tell if/when F crossesthe axis; more about that later.

..x

.

y

..1

..2

..3

..4

..5

..6

.......f

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

".

.

.

"

.

IP

.

max

.

IP

.

min

..

....

Page 113: Lesson 23: Antiderivatives (slides)

Could you repeat the question?ProblemBelow is the graph of a func on f. Draw the graph of thean deriva ve for f with F(1) = 0.

Solu on

I We start with F(1) = 0.I Using the sign chart, we draw arcswith the specified monotonicity andconcavity

I It’s harder to tell if/when F crossesthe axis; more about that later.

..x

.

y

..1

..2

..3

..4

..5

..6

.......f

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

".

.

.

"

.

IP

.

max

.

IP

.

min

...

...

Page 114: Lesson 23: Antiderivatives (slides)

Could you repeat the question?ProblemBelow is the graph of a func on f. Draw the graph of thean deriva ve for f with F(1) = 0.

Solu on

I We start with F(1) = 0.I Using the sign chart, we draw arcswith the specified monotonicity andconcavity

I It’s harder to tell if/when F crossesthe axis; more about that later.

..x

.

y

..1

..2

..3

..4

..5

..6

.......f

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

".

.

.

"

.

IP

.

max

.

IP

.

min

...

...

Page 115: Lesson 23: Antiderivatives (slides)

Could you repeat the question?ProblemBelow is the graph of a func on f. Draw the graph of thean deriva ve for f with F(1) = 0.

Solu on

I We start with F(1) = 0.I Using the sign chart, we draw arcswith the specified monotonicity andconcavity

I It’s harder to tell if/when F crossesthe axis; more about that later.

..x

.

y

..1

..2

..3

..4

..5

..6

.......f

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

".

.

.

"

.

IP

.

max

.

IP

.

min

....

..

Page 116: Lesson 23: Antiderivatives (slides)

Could you repeat the question?ProblemBelow is the graph of a func on f. Draw the graph of thean deriva ve for f with F(1) = 0.

Solu on

I We start with F(1) = 0.I Using the sign chart, we draw arcswith the specified monotonicity andconcavity

I It’s harder to tell if/when F crossesthe axis; more about that later.

..x

.

y

..1

..2

..3

..4

..5

..6

.......f

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

".

.

.

"

.

IP

.

max

.

IP

.

min

....

..

Page 117: Lesson 23: Antiderivatives (slides)

Could you repeat the question?ProblemBelow is the graph of a func on f. Draw the graph of thean deriva ve for f with F(1) = 0.

Solu on

I We start with F(1) = 0.I Using the sign chart, we draw arcswith the specified monotonicity andconcavity

I It’s harder to tell if/when F crossesthe axis; more about that later.

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Page 118: Lesson 23: Antiderivatives (slides)

Could you repeat the question?ProblemBelow is the graph of a func on f. Draw the graph of thean deriva ve for f with F(1) = 0.

Solu on

I We start with F(1) = 0.I Using the sign chart, we draw arcswith the specified monotonicity andconcavity

I It’s harder to tell if/when F crossesthe axis; more about that later.

..x

.

y

..1

..2

..3

..4

..5

..6

.......f

.

F

.

shape

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4

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6

.

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max

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min

......

Page 119: Lesson 23: Antiderivatives (slides)

Could you repeat the question?ProblemBelow is the graph of a func on f. Draw the graph of thean deriva ve for f with F(1) = 0.

Solu on

I We start with F(1) = 0.I Using the sign chart, we draw arcswith the specified monotonicity andconcavity

I It’s harder to tell if/when F crossesthe axis; more about that later.

..x

.

y

..1

..2

..3

..4

..5

..6

.......f

.

F

.

shape

..

1

..

2

..

3

..

4

..

5

..

6

.

"

.

".

.

.

"

.

IP

.

max

.

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.

min

......

Page 120: Lesson 23: Antiderivatives (slides)

OutlineWhat is an an deriva ve?

Tabula ng An deriva vesPower func onsCombina onsExponen al func onsTrigonometric func onsAn deriva ves of piecewise func ons

Finding An deriva ves Graphically

Rec linear mo on

Page 121: Lesson 23: Antiderivatives (slides)

Say what?

I “Rec linear mo on” just means mo on along a line.I O en we are given informa on about the velocity oraccelera on of a moving par cle and we want to know theequa ons of mo on.

Page 122: Lesson 23: Antiderivatives (slides)

Application: Dead Reckoning

Page 123: Lesson 23: Antiderivatives (slides)

Application: Dead Reckoning

Page 124: Lesson 23: Antiderivatives (slides)

ProblemSuppose a par cle of mass m is acted upon by a constant force F.Find the posi on func on s(t), the velocity func on v(t), and theaccelera on func on a(t).

Solu on

I By Newton’s Second Law (F = ma) a constant force induces aconstant accelera on. So a(t) = a =

Fm.

I Since v′(t) = a(t), v(t)must be an an deriva ve of theconstant func on a. So

v(t) = at+ C = at+ v0

where v0 is the ini al velocity.I Since s′(t) = v(t), s(t)must be an an deriva ve of v(t),meaning

s(t) =12at2 + v0t+ C =

12at2 + v0t+ s0

Page 125: Lesson 23: Antiderivatives (slides)

ProblemSuppose a par cle of mass m is acted upon by a constant force F.Find the posi on func on s(t), the velocity func on v(t), and theaccelera on func on a(t).

Solu on

I By Newton’s Second Law (F = ma) a constant force induces aconstant accelera on. So a(t) = a =

Fm.

I Since v′(t) = a(t), v(t)must be an an deriva ve of theconstant func on a. So

v(t) = at+ C = at+ v0

where v0 is the ini al velocity.I Since s′(t) = v(t), s(t)must be an an deriva ve of v(t),meaning

s(t) =12at2 + v0t+ C =

12at2 + v0t+ s0

Page 126: Lesson 23: Antiderivatives (slides)

ProblemSuppose a par cle of mass m is acted upon by a constant force F.Find the posi on func on s(t), the velocity func on v(t), and theaccelera on func on a(t).

Solu on

I By Newton’s Second Law (F = ma) a constant force induces aconstant accelera on. So a(t) = a =

Fm.

I Since v′(t) = a(t), v(t)must be an an deriva ve of theconstant func on a. So

v(t) = at+ C = at+ v0

where v0 is the ini al velocity.

I Since s′(t) = v(t), s(t)must be an an deriva ve of v(t),meaning

s(t) =12at2 + v0t+ C =

12at2 + v0t+ s0

Page 127: Lesson 23: Antiderivatives (slides)

ProblemSuppose a par cle of mass m is acted upon by a constant force F.Find the posi on func on s(t), the velocity func on v(t), and theaccelera on func on a(t).

Solu on

I By Newton’s Second Law (F = ma) a constant force induces aconstant accelera on. So a(t) = a =

Fm.

I Since v′(t) = a(t), v(t)must be an an deriva ve of theconstant func on a. So

v(t) = at+ C = at+ v0

where v0 is the ini al velocity.I Since s′(t) = v(t), s(t)must be an an deriva ve of v(t),meaning

s(t) =12at2 + v0t+ C =

12at2 + v0t+ s0

Page 128: Lesson 23: Antiderivatives (slides)

An earlier HatsumonExample

Drop a ball off the roof of the Silver Center. What is its velocity whenit hits the ground?

Solu onAssume s0 = 100m, and v0 = 0. Approximate a = g ≈ −10. Then

s(t) = 100− 5t2

So s(t) = 0 when t =√20 = 2

√5. Then

v(t) = −10t,

so the velocity at impact is v(2√5) = −20

√5m/s.

Page 129: Lesson 23: Antiderivatives (slides)

An earlier HatsumonExample

Drop a ball off the roof of the Silver Center. What is its velocity whenit hits the ground?

Solu onAssume s0 = 100m, and v0 = 0. Approximate a = g ≈ −10. Then

s(t) = 100− 5t2

So s(t) = 0 when t =√20 = 2

√5. Then

v(t) = −10t,

so the velocity at impact is v(2√5) = −20

√5m/s.

Page 130: Lesson 23: Antiderivatives (slides)

Finding initial velocity fromstopping distance

Example

The skid marks made by an automobile indicate that its brakes werefully applied for a distance of 160 before it came to a stop.Suppose that the car in ques on has a constant decelera on of20 ft/s2 under the condi ons of the skid. How fast was the cartraveling when its brakes were first applied?

Solu on (Setup)

I While braking, the car has accelera on a(t) = −20I Measure me 0 and posi on 0 when the car starts braking. Sos(0) = 0.

I The car stops at me some t1, when v(t1) = 0.I We know that when s(t1) = 160.I We want to know v(0), or v0.

Page 131: Lesson 23: Antiderivatives (slides)

Finding initial velocity fromstopping distance

Example

The skid marks made by an automobile indicate that its brakes werefully applied for a distance of 160 before it came to a stop.Suppose that the car in ques on has a constant decelera on of20 ft/s2 under the condi ons of the skid. How fast was the cartraveling when its brakes were first applied?

Solu on (Setup)

I While braking, the car has accelera on a(t) = −20

I Measure me 0 and posi on 0 when the car starts braking. Sos(0) = 0.

I The car stops at me some t1, when v(t1) = 0.I We know that when s(t1) = 160.I We want to know v(0), or v0.

Page 132: Lesson 23: Antiderivatives (slides)

Finding initial velocity fromstopping distance

Example

The skid marks made by an automobile indicate that its brakes werefully applied for a distance of 160 before it came to a stop.Suppose that the car in ques on has a constant decelera on of20 ft/s2 under the condi ons of the skid. How fast was the cartraveling when its brakes were first applied?

Solu on (Setup)

I While braking, the car has accelera on a(t) = −20I Measure me 0 and posi on 0 when the car starts braking. Sos(0) = 0.

I The car stops at me some t1, when v(t1) = 0.

I We know that when s(t1) = 160.I We want to know v(0), or v0.

Page 133: Lesson 23: Antiderivatives (slides)

Finding initial velocity fromstopping distance

Example

The skid marks made by an automobile indicate that its brakes werefully applied for a distance of 160 before it came to a stop.Suppose that the car in ques on has a constant decelera on of20 ft/s2 under the condi ons of the skid. How fast was the cartraveling when its brakes were first applied?

Solu on (Setup)

I While braking, the car has accelera on a(t) = −20I Measure me 0 and posi on 0 when the car starts braking. Sos(0) = 0.

I The car stops at me some t1, when v(t1) = 0.I We know that when s(t1) = 160.I We want to know v(0), or v0.

Page 134: Lesson 23: Antiderivatives (slides)

Implementing the SolutionIn general,

s(t) = s0 + v0t+12at2

Since s0 = 0 and a = −20, we have

s(t) = v0t− 10t2

v(t) = v0 − 20t

for all t.

Plugging in t = t1,

160 = v0t1 − 10t210 = v0 − 20t1

We need to solve these two equa ons.

Page 135: Lesson 23: Antiderivatives (slides)

Implementing the SolutionIn general,

s(t) = s0 + v0t+12at2

Since s0 = 0 and a = −20, we have

s(t) = v0t− 10t2

v(t) = v0 − 20t

for all t. Plugging in t = t1,

160 = v0t1 − 10t210 = v0 − 20t1

We need to solve these two equa ons.

Page 136: Lesson 23: Antiderivatives (slides)

SolvingWe have

v0t1 − 10t21 = 160 v0 − 20t1 = 0

I The second gives t1 = v0/20, so subs tute into the first:

v0 ·v020

− 10( v020

)2= 160

I Solve:

v2020

− 10v20400

= 160

2v20 − v20 = 160 · 40 = 6400

So v0 = 80 ft/s ≈ 55mi/hr

Page 137: Lesson 23: Antiderivatives (slides)

SolvingWe have

v0t1 − 10t21 = 160 v0 − 20t1 = 0

I The second gives t1 = v0/20, so subs tute into the first:

v0 ·v020

− 10( v020

)2= 160

I Solve:

v2020

− 10v20400

= 160

2v20 − v20 = 160 · 40 = 6400

So v0 = 80 ft/s ≈ 55mi/hr

Page 138: Lesson 23: Antiderivatives (slides)

SolvingWe have

v0t1 − 10t21 = 160 v0 − 20t1 = 0

I The second gives t1 = v0/20, so subs tute into the first:

v0 ·v020

− 10( v020

)2= 160

I Solve:

v2020

− 10v20400

= 160

2v20 − v20 = 160 · 40 = 6400

So v0 = 80 ft/s ≈ 55mi/hr

Page 139: Lesson 23: Antiderivatives (slides)

Summary of Antiderivatives so farf(x) F(x)

xr, r ̸= 11

r+ 1xr+1 + C

1x= x−1 ln |x|+ Cex ex + C

ax1ln a

ax + Cln x x ln x− x+ C

loga xx ln x− x

ln a+ C

sin x − cos x+ Ccos x sin x+ Ctan x ln | tan x|+ C

Page 140: Lesson 23: Antiderivatives (slides)

Final Thoughts

I An deriva ves are auseful concept, especiallyin mo on

I We can graph anan deriva ve from thegraph of a func on

I We can computean deriva ves, but notalways

..x

.

y

..1

..2

..3

..4

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..6

....... f.......F

f(x) = e−x2

f′(x) = ???