Hi, dimelychime. Welcome to the forum!

The first solution looks correct (this is the Fundamental Theorem of Calculus along with the chain rule).

I got for the second problem and checked this a couple times. Note: I used the substitution to find an antiderivative.

I didn't see an attachment with work for the second problem so I don't know where our differences may be.

Let me know if you try it again. If there are still differences, I will write up more details in a later post. Good luck!