Question

Which first step most directly prepares the expression below?

$$\sqrt{16-x^{2}},\quad -4<x<4$$

Accepted Answer

$$x=4\sin(	heta),\quad dx=4\cos(	heta)\,d	heta$$

Answer

$$x=4\sec(	heta),\quad dx=4\sec(	heta)	an(	heta)\,d	heta$$

Answer

$$x=4	an(	heta),\quad dx=4\sec^{2}(	heta)\,d	heta$$

Answer

$$x=4\sin(	heta),\quad dx=4\sin(	heta)\,d	heta$$

Practice: Integration - Technique First Step