Question

For what numbers theta is f(theta)=cot(theta) not defined?

f(theta)=cot(theta) is not defined for numbers that are (even multiples, odd multiples, multiples) of (90*, 180*, 45*).

Answer 1

cot theta = cos theta / sin theta

when sin theta = 0, the function is undefined.

So for what values of theta that satisfy the equation sin theta = 0?

Answer 2

So it is undefined for 0 +kpi