# High School Math : Using the Unit Circle

## Example Questions

### Example Question #1 : Using The Unit Circle

What is ?

Explanation:

If you examine the unit circle, you'll see that the the . If you were to graph a sine function, you would also see that it crosses through the point .

### Example Question #2 : Using The Unit Circle

What is ?

Explanation:

If you look at the unit circle, you'll see that . You can also think of this as the cosine of , which is also .

### Example Question #2 : Using The Unit Circle

What is ?

Explanation:

If you look at the unit circle, you'll see that . You can also think of this as the sine of , which is also .

### Example Question #3 : Using The Unit Circle

What is ?

Explanation:

Using the unit circle, . You can also think of this as the cosine of , which would also be .

### Example Question #4 : Using The Unit Circle

What is ?

Explanation:

Using the unit circle, you can see that . If you were to graph a cosine function, you would also see that it crosses through the point .

### Example Question #2 : Using The Unit Circle

What is ?

Explanation:

Using the unit circle, . You can also think of this as the sine of , which would also be .

### Example Question #3 : Using The Unit Circle

What is ?

Explanation:

Using the unit circle, you can see that the . Since the angle is in Qudrant II, sine is positive and cosine is negative.

### Example Question #4 : Using The Unit Circle

What is ?

Explanation:

Using the unit circle, . You can also think of this as the sine of , which would also be .

### Example Question #21 : Graphing The Sine And Cosine Functions

What is ?

Explanation:

If you examine the unit circle, you'll see that that

What is ?