What is the period of the parent cosine function, y = cos (x)

What is the period of the parent cosine function, y = cos (x) ?

360 degrees

What is the period of the cosine function shown in the graph?

1080 degrees

Which type of transformation of the parent function is shown by the graph?

horizontal stretch

2π

Step-by-step explanation:

This is a little something you have to memorize, but you could derive it from the equation pb = 2π. In the parent function, the b value is 1, so the period, p, is equal to 2π/1 or just 2π.