Question

How to solve `cos x < |1|`?

Answer 1

See below.

Explanation:

`cos x <1`, `cos x > -1`. In the interval `[0 , 2pi ]` `cosx = 1` at 0 and `cosx= -1` at `pi`. So the range is:

`0 < x < pi` and `pi < x < 2pi`