Question

Please help!! In radians, what is the period of the function y = .5cos5x

pi/5

(3pi)/2

(2pi)/5

pi/2

Answer 1

(2pi)/5

Explanation:

The cosine function cos(x) has a period of 2*pi.

If we change the argument of the cosine, the new argument will have a period of 2*pi. If the new argument is 5x, we have that the period will be:

5x = 2*pi

x = 2*pi/5

The period of this function will be (2pi)/5, because for every (2pi)/5 change in the value of x, the function will have the same value. The value of 5 multiplying the cosine does not interfere in the period.