1. The problem statement, all variables and given/known data I got this expression while solving a problem. (y+1)/(y-1)=sin2x/sin2a we need to find the range of y 2. Relevant equations 3. The attempt at a solution here y=(sin2x+sin2a)/(sin2x-sin2a) Numerator of RHS lies between sin2a-1 and 1+sin2a Denominator lies between -1-sin2a and 1-sin2a so RHS lies between (sin2a-1)/(-1-sin2a) and (1+sin2a)/(1-sin2a) on solving I got y lies between tan^2 (45-a) and tan^2 (45+a) but the answer is opposite (i.e. y does not lie between them). Please help.