Question

What is wrong with the statement `tan90° = 1/(cot90°)`?

Answer 1

The tangent of 90 degrees is not defined, and you can't divide by cot 90° which is zero.

Answer 2

`tan(90)` `=` `sin(90)/cos (90)`

Explanation:

`tan 90°` is not the cotangent of `90°`