# Homework Help: Integration of many variables

1. May 11, 2009

### soopo

1. The problem statement, all variables and given/known data
Let
F(x) = integral from x to 1 ( $$3t^3 - x^2 t ) dt$$

1. Calculate F'(x)

3. The attempt at a solution

I know the answer is

x^3 + x.

However, I am not sure how it is obtained.

I know about implicit differentian, but I have never done implicit integration.

How can you solve the problem?

2. May 11, 2009

### CompuChip

In this case, you can simply work out the integral.
Do the t-integration, it will give you
$$\frac34 t^4 - \frac12 x^2 t^2$$
evaluated between the boundaries t = x and t = 1.
Then differentiate.

3. May 11, 2009

### soopo

Thank you for your answer!

The solution was much easier than I first thought.

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