- #1

MMM

- 8

- 0

## Homework Statement

Hello, I'm having trouble determining what I make u equal with most integrals that revolve around the inverse trig functions.

I knew what to let u equal in this problem ##x/\sqrt{1-x^4}## I let it equal ##x^2## and correctly solved the problem.

The problems I'm having trouble with, are problems like ##1/(a^2 + x^2)## the book said to substitute u = x/a and when I did that I found the correct answer. Sadly I had no idea that is what I was supposed to substitute.

Here is another problem I had no idea what to substitute ##1/(a^2 + (b^2)(x^2))## the book said to substitute u = bx/a and when I did that I got the correct answer. I just need some guidance to understand the kinda substitutions I need to make regarding integration involving inverse trig functions. Any help is greatly needed and highly appreciated, thanks.

## Homework Equations

## The Attempt at a Solution

I solved the stated problems with the book's help on what to substitute. I just had no idea on to what to substitute.