How do I use the product rule for derivatives?
Imagine a function f(x)=g(x)*h(x) [that is, two functions multiplied together]
To find the derivative, f'(x)=g'(x)*h(x) + g(x)*h'(x)
For example, f(x) = (3x2)*(cos x ) [g(x)=3x2 , h(x)=cosx]
f'(x) = (6x)(cos x ) + (3x2)(-sin x )
=6xcos(x) - 3x2sin(x)
JW
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