Question

How do you evaluate `cos(cos^-1(1.1))`?

Answer 1

`cos(cos^-1(1.1))` cannot be evaluated

Explanation:

`y=cos^-1(x)` is defined as the number `y` for which `cos y = x`.

As the range of `cos x` is `[-1,1]` there is no number for which `cos y = 1.1`

Therefore `cos(cos^-1(1.1))` is not defined.