crms calculus 2010 january 22, 2010
DESCRIPTION
Differentiability implies ContinuityTRANSCRIPT
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Earnyourturns!
Differentiability and Continuity
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Section 46: Differentiability and Continuity
f(c) exists
exists
A function f(x) is continuous on an intervalif and only if it is continuous at each xvalue in the interval.
A function f(x) is continuous if and only if f(x) is continuous at each xvalue in its domain.
Slope of tangent at point x = c.
Instantaneous rate of change at x = c.
A function f(x) is differentiable at a point x = c,if and only if f '(c) exists.
A function f(x) is differentiable on an intervalif and only if it is differentiable for each xvalue in the interval.
A function f(x) is differentiable if and only if it is differentiable at each xvalue in its domain.
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Review: Conditional Statements
Property:P Q
If Socrates is a man, then he is mortal.
Contrapositive: If he is not mortal, then Socrates is not a man.~ Q ~ P
Inverse: If Socrates is not a man, then he is not mortal.~ P ~ Q
Converse: If he is mortal, then Socrates is a man.PQ
mortal Definition: subject to death, destined to die.
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If function f is NOT continuous at x = c,then function f is NOT differentiable at x = c.
If function f is NOT differentiable at x = c,then function f is NOT continuous at x = c.
"smooth"(Beautiful "S" turns down the slope)
"hang"tangent
cannot"hang"tangent
Not "smooth"(Switchbacks up the slope)
If function f is continuous at x = c,then function f is differentiable at x = c.
tangent is vertical at x = c
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Cusp
Continuity does NOT imply differentiability
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vertical
infinite discontinuity
Continuity does NOT imply differentiability
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horizontal
removablediscontinuity
removable discontinuity
None. No point to "hang" tangent on.
If a function is NOT continuous at a point x = c,then the function is NOT differentiable at the point x = c.
(contrapositive of property)