How do you find the amplitude and period of a function #y=cos²(x)#?
First, simply graph each function ... the blue line is the new function and the red line is cos x .
Since this function is squared, it must always be positive. Also, since cos x fluctuates between -1 and 1, then squaring it, the new function will fluctuate between 0 and 1.
The period will also be cut in half .
hope that helped