25 - Substitution with x = asin(theta)

Whenever you have to integrate a function that has some form of the expression , you can substitute for , which lets you play around with the pythagorean identity.

Do the substitution!

Suppose you have .

Reminder that we have theta now.

When we perform this substitution, we can't integrate for dx, so we will have to integrate for instead. We will need to "convert" this somehow.

Much like we did in u-substitution, where was the , will be what we multiply our integral with.

Let's do an example!

Cool, right?

Just kidding, i know this is psychological torture. But good job so far!

26 - Substitution with x = atan(theta)

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