# Precalculus : Find the Amplitude of a Sine or Cosine Function

## Example Questions

### Example Question #1 : Find The Amplitude Of A Sine Or Cosine Function

What is the amplitude of ?

Explanation:

For any equation in the form , the amplitude of the function is equal to .

In this case,  and , so our amplitude is .

### Example Question #2 : Find The Amplitude Of A Sine Or Cosine Function

What is the amplitude of ?

Explanation:

The formula for the amplitude of a sine function is  from the form:

.

In our function, .

Therefore, the amplitude for this function is .

### Example Question #3 : Find The Amplitude Of A Sine Or Cosine Function

Find the amplitude of the following trig function:

Explanation:

Rewrite  so that it is in the form of:

The absolute value of  is the value of the amplitude.

### Example Question #4 : Find The Amplitude Of A Sine Or Cosine Function

Find the amplitude of the function.

Explanation:

For the sine function

where

the amplitude is given as  .

As such the amplitude for the given function

is

.

### Example Question #1 : Period And Amplitude

Which of the given functions has the greatest amplitude?