(adsbygoogle = window.adsbygoogle || []).push({}); 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.

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# Homework Help: Trigonometric Identities

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