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L(x)=sqrt(x)*f(x)

f(9)=3

F'(9)=(-4)

find L'(9)

I think I need to use the product rule:

L'(9)=0.5x^(-0.5)*f(x)+f'(x)*sqrt(x)

L'(9)=(1/6)*3+(-4)*3

L'(9)=-11.5

Also, what if the question asked for f^3(x), how would I set that up?

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# Homework Help: Evaluating functions

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