So now it's interesting. We need to figure out what h prime of three is. So we can figure out what h of three is, and then we can use that to figure out what g prime of whatever h, g prime of h of three is. And so we should be able to figure out h prime of x. Or we could just rewrite it this way. We could rewrite that h prime of x is equal to, is equal to one over g prime of h of x. Now in some circles, they might encourage you to memorize this, and maybe for the sake of doing this exercise on Khan Academy, you might want to memorize it.