Given the task definition and input, reply with output. In this task you're given a question and you have to paraphrase the question to create the output question while retaining the meaning of the original question.

What is cot Pi/2: if cot x = 1/tan x then it seems it should be undefined, if we consider cot x = cos x / sin x it should be 0?
How do you make your own waterbed conditioner?