Hey, I have a crappy community college professor and apparently I am not smart enough to figure out the parts she didn't teach.(adsbygoogle = window.adsbygoogle || []).push({});

the definite inegral of (ln x)^2 - 1 (part of a geometry problem)

from e^-1 to e

I tried this:

[(x ln x - x)^3]/3 - x

And got 2.48, but looking at the graph it looks like it should be about 1.5.

This is just a homework problem, but none of the class can get it.

I also have another question on a different problem.

a definite integral from -.5 to .5

SQRT[1-(2 cos (pi*x))^2]

I got as far as SQRT[1 - 4pi^2sin^2(pi*x) and I have NO idea how to integrate that.

None of the class could figure out this one either.

My calculus teacher is about 75 years old, and she shouldn't be teaching, I feel like I haven't learned anything except what I have taught myself.

Thank you for any help!

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Need help with 2 integrals.

**Physics Forums | Science Articles, Homework Help, Discussion**