# Differentiation: Product rule and composite rule

imy786

## Homework Statement

Use differentiation to verify that the following integrals are correct (where a is not = 0 is a constant and c is an arbitrary constant

(a) integrate xsinax dx= ( −x/a ) (cosax) +(1/a2) sinax+c

(b) integrate tanax dx=(−1/a) ln(cosax)+c

## Homework Equations

Composite rule dy/dx = (dy/du) (du/dx)

## The Attempt at a Solution

Im not getting the right solution after diffrenting.

attached are my solutions

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Gold Member
I don't see an attachment. For the first problem, you also need the product rule. For the second one, you need to use the chain rule twice.

Last edited:
Mentor
What both of you are referring to as the "composition" rule, most books that I've seen call the chain rule.

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