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.