# Math Help - Second Fundamental Theorem

1. ## Second Fundamental Theorem

I need help with his problem. The integral is 2 through X and for Cos t/t solve using the second fundamental theorem?

The other one is 1 through 3x^2 for tan t

sorry I am new here and dont know how to use the integrand sign.

2. Originally Posted by Iron Angel
I need help with his problem. The integral is 2 through X and for Cos t/t solve using the second fundamental theorem?
Are you tryin' to find the derivative of

$f(x)=\int_2^x\frac{\cos t}t\,dt?$

In that case we have

$f'(x)=\frac{\cos x}x,$ and we're done.

Originally Posted by Iron Angel
The other one is 1 through 3x^2 for tan t
Apply the same as the previous problem.

3. yeah that is exactly what i was looking for thanks!!. So on the second one it would be 6x tan 3x^2 because of the chain rule.

4. That's correct.