I'm not sure this is the right forum, but here goes:

Depending on , find where the expression

is greater than zero, less than zero and equal to zero.

I suppose the first step is to write it as

.

So, if , than the expression is zero, no matter what the is.

Also, if or , , so it comes down to whether is 0, <0 or >0.

I've tried and tried, but no luck.

Please, help.