# How to find the amplitude of a trigonometric function?

The amplitude of a trig function defines how much the graph is going to be getting stretched or compressed on the `y-axis`

. Take for example the following function.

$$sin(x)$$

On this function, no compression or stretching on the `y-axis`

is happening but if you add an amplitude of 3 the amplitude is going to stretch the function values up to the 3 mark on the `y-axis`

.

$$3sin(x)$$

The same concept applies to compressing the function for a value that is smaller than one.

$$\frac { 1 }{ 2 }sin(x)$$

If you now overlay all three functions together you will see that the function still have the same intercepts on the `x-axis`

just the values on the `y-axis`

have changed everything else has remained the same.