# Hi guys! Can anyone help me solve this question? Just started learning this chapter so I'm not quite familiar with this : Given sin theta = 1/2 and that theta is an acute angle. Evaluate sin 2 theta & sec 2 theta.

##### 1 Answer

There are two ways. First the shortcut, the acute angle whose sine is

#### Explanation:

Sure, we're happy to help. The first way was a trick, an angle we knew,

Let's solve it in general, say we're given

Let's be definite and say the problem tells us to chose the positive sign, like the acute

Then we're asked for

We can check our formulas by trying