calc 2 cheat sheet
DESCRIPTION
Cheat sheet for Calculus 2 including charts and equations with brief explanations and examples.TRANSCRIPT
The Most Important Derivatives and Antiderivatives:
The Sum Rule, the Constant Multiple Rule and the Power Rule for Integration:Sum Rule for Integration – integrate long expressions term by term. Expressed formally:
Constant Multiple Rule for Integration – move a constant outside of an integral before you integrate. Expressed in symbols:
Power Rule for Integration – integrate any real power of x (except -1). Expressed formally:
where n ≠ –1,
Solve Integrals with Variable Substitution:1. Declare a variable u, set it equal to an algebraic
expression that appears in the integral, and then substitute u for this expression in the integral.
2. Differentiate u to find dudx
, then isolate all x
variables on one side of the equal sign.3. Make another substitution to change dx and all
other occurrences of x in the integral to an expression that includes du.
4. Integrate by using u as your new variable of integration.
5. Express this answer in terms of x.
Integration by Parts:Gives you the option to break down product of two functions to its factors and integrate in altered form. Follow these steps:1. Decompose the entire integral (including dx) into
two factors.2. Let the factor without dx equal u and the factor
with dx equal dv.3. Differentiate u to find du; integrate dv to find v.4. Use the formula: 5. Evaluate the right side of this equation to solve the
integral.
Compound Functions Where Inner Function is ax + b :Integrate the outer function f, and the inner function g(x) is of the form ax + b — it differentiates to a constant. Here are some examples:
Compound Functions Where Inner Function is ax:Integrate the outer function f, and the inner function g(x) is of the form ax — it differentiates to a constant. Here are some examples:
Chapter 7: Transcendental FunctionsSection 7.1 – Inverse Functions and Their Derivatives: One-to-One functions – f(x) is one-to-one on a
domain D if f(x1) ≠ f(x2) whenever x1 ≠ x2 in D.Function y = f(x) one-to-one if graph intersects each horizontal line at most once.
Inverse functions – suppose f is one-to-one function on domain D with range R, inverse function f -1 defined by f -1(b) = a if f(a) = b. Domain of f -1 is R and range is D.
Finding inverse – passing from f to f -1 summarized as two-step procedure:1. Solve equation y = f(x) for x, giving x = f -1(y) where x is function of y.2. Interchange x and y, giving formula y = f -1(x).
Derivatives of inverses of differentiable functions – derivatives are reciprocals of one another slopes
are reciprocal: (f -1)’(b) = 1f'(a)
or (f -1)’(b) =
1f'( f-1(b)¿
¿.
Derivative rule for inverses – if f has interval I as domain and f’(x) exists and is never zero on I, then f -1 is differentiable at every point in its domain (range of f). Value (f -1)’ at point b in domain of f -1 is reciprocal of value of f’ at point a = f -1(b):
(f -1)’(b) = 1f'( f-1(b)¿
¿ or
d f-1
dx∨ ❑
x = b=1dfdx
∨ ❑x = f-1(b)
.
Section 7.2 – Natural Logarithms: Definition of natural logarithm function – natural
logarithm of any positive number x, written as ln x, is defined as integral. Natural logarithm is function
given by ln x = ∫-1
x 1t
dt , x > 0.
Number e is number in the domain of natural
logarithm satisfying ln(e) = 1 ∫1
e 1t
dt = 1.
Derivative of y = ln x: ddx
ln x =
ddx ∫
1
x 1t
dt = 1x
for every positive value x, ddx
ln x = 1x
,
chain rule extends formula for positive functions u(x):
ddx
ln u = ddu
ln u ∙dudx
so…
ddx
ln u = 1u
dudx
, u > 0
ddx
ln|1x|, x ≠ 0
Properties of logarithms1. Product rule: ln bx = ln b + ln x
2. Quotient rule: ln bx
= ln b – ln x
3. Reciprocal rule: ln 1x
= -ln x
4. Power rule: ln x r = r ln x
The integral ∫1u
du = ln |u| + C if u = f(x),
then ∫ f'(x)f(x)
dx = ln |f(x)| + C whenever
f(x) differentiable function that is never zero.
∫sin x dx = -cos x + C
∫ tan x dx = -ln |cos x| + C
∫cos x dx = sin x + C ∫cot x dx =
ln |sin x| + C
∫sec x dx = ln |sec x + tan x| + C
∫csc x dx = -ln |csc x + cot x| + C
Section 7.3 – Exponential Functions: Inverse of ln x and the number e – for every real
number x, we define natural exponential function to be e x = exp x.Inverse equations for e x and ln x:e ln x = x (all x > 0) and… ln (e x) = x (all x)
Derivative and integral of e x : if u is any
differentiable function of x, then ddx
e u = e u
dudx .
General antiderivative of the exponential function:
∫e udu = e u + C
For all numbers x, x1 and x2, the natural exponential e x obeys the following laws:
1. e x1∙e x2 = e x1+x 2 3. e x1
e x2 =
e x 1−x2
2. e-x = 1e x 4. (ex1) r = e r x1, if r is
rational The general exponential function ax – for any
numbers a > 0 and x, the exponential function with base a is: a x = e x ln a when a = e, the definition
gives a x = e x ln a = e x ln e = ex ∙ 1 = e x in particular,
a n ∙ a -1 = a n-1
Proof of the power rule (general version) – for any x > 0 and for any real number n, x n = e n ln x General power rule for derivatives – for x > 0 and
any real number n, ddx
x n = nx n-1 ; if x ≤ 0, then
the formula holds whenever the derivative, x n, and
x n-1 all exist so… ddx
x n = ddx
e n ln x = nx n-1
Differentiate f(x) = x x, x > 0:
f’(x) = ddx
(e x ln x) = e x ln x ddx
(x ln x) = e x ln x (ln x +
x ∙1x
)
= x x (ln x + 1) The derivative of a u :
ddx
a x = ddx
e x ln a = ddx
(x ln a) = a x ln a
if a = e, then ln a = 1 so…
derivative of a x simplifies to ddx
e x = e x ln e = e x
If a > 0 and u is differentiable function of x, then a u
is differentiable function of x and ddx
a u = a u ln a
dudx
∫ a u du =
a u
ln a + C
Logarithms with base a – for any positive number a ≠ 1, log a x is the inverse function of a x
When a = e, log e x = inverse of e x = ln x.
Rules for base a logarithms – for any numbers x > 0 and y > 01. Product rule: log a xy = log a x + log a y
2. Quotient rule: log a
xy
= log a x – log a y
3. Reciprocal rule: log a 1y
= -log a y
4. Power rule: log a x y = y log a x Inverse equations for a x and log
a x:
a loga x = x (x > 0) and… log a x (ax) = x (all x)
log a x = ln xln a
ddx
log a u = ddx
(ln uln a
) = 1ln a
ddx
(ln u)
Derivatives and integrals involving log a x:
ddx
(log a u) = ddx
(ln uln a
) = 1ln a
ddx
(ln u) = 1ln a
∙ 1u
dudx
ddx
(log a u) = 1ln a
∙ 1u
dudx