Question

Question #91dad

Answer 1

Not sure what the question is but
if it is to identify the "excluded values"
then `x !in {k*pi|kinZZ}`

Explanation:

Since the function definition requires division by `sin x`
then `sin x != 0`
`rarr x != k* pi` for any `kinZZ`

Note that if `k` is an odd integer
the function evaluates as a removable discontinuity.