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## Homework Statement

Hello!

The task is to express the exact answer in interval notation, restricting your attention to -2π ≤ x ≤ 2π.

## Homework Equations

The given inequality:

cos(x) ≤ 5/3

## The Attempt at a Solution

I have only one doubt here, and I don't see my mistake.

I see that if cos(x) was strictly less than (namely <) 5/3, then the answer is [-2π, 2π].

But the inequality says that cos(x) is less or

**equal to**5/3, but cos(x) can't be equal to any number larger than 1, because its range is [-1, 1]. Why then this inequality is considered having any solutions at all (because of this "equal to" sign)?

Thank you!