state the domain and range of the function and sketch a graph showing two periods. y = cos²x what is the…

state the domain and range of the function and sketch a graph showing two periods. y = cos²x what is the domain? (type your answer in interval notation.)
Answer
Explanation:
Step1: Recall cosine domain property
The function $y = \cos x$ has a domain of all real - numbers. For $y=\cos^{2}x$, since we are just squaring the output of the cosine function, there are no restrictions on the input $x$. The domain of $y = \cos x$ is $x\in(-\infty,\infty)$. Squaring it does not change the domain.
Step2: Write domain in interval notation
The interval notation for all real numbers is $(-\infty,\infty)$.
Answer:
$(-\infty,\infty)$