Dewight needs to restrict the domain of the cosine function so that the inverse is a function. Which description best describes how she could restrict the domain?

Question

So that y = cos(x) is always decreasing

So that y = cos(x) only has one maximum

So that y = cos(x) only has one minimum

So that y = cos(x) only has two maximum

I chose B

Answer 1

Still no. try (A)

If there is a min or max, the curve folds back on itself, so it is no longer invertible. It fails the horizontal line test.