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рдкреНрд░рд╢реНрди
`sqrt((1-cos theta)/(1+cos theta)) = (cosec theta - cot theta)`
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рдЙрддреНрддрд░
LHS = `sqrt((1-cos theta)/(1+ cos theta))`
=`sqrt(((1-cos theta))/((1+cos theta)) xx ((1- cos theta))/((1 - cos theta))`
=`sqrt((1-cos theta)^2 / (1-cos^2 theta))`
=`sqrt((1-cos theta)^2)/(sin^2 theta)`
=`(1-cos theta)/sin theta`
=`1/sin theta - cos theta/ sin theta`
=(ЁЭСРЁЭСЬЁЭСаЁЭСТЁЭСР ЁЭЬГ − cot ЁЭЬГ)
= RHS
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