Prove : Cos A - Sin A +1 / Cos A +Sin A -1 = Cosec A + Cot A using the identity cosec2A = 1+cot2A
Cos A - Sin A + 1/ Cos A + Sin A - 1 dividing in numerator & denominator with Sin A
Cot A - 1 + Cosec A / Cot A - Cosec A + 1
now putting 1= Cosec^2 - Cot ^2
= (Cot A + Cosec A) - (Cosec2 A - Cot2 A) / (Cot A - Cosec A + 1)
= (Cot A + Cosec A) [1 - Cosec A + Cot A) / (Cot A - Cosec A + 1)]
= (Cot A + Cosec A) RHS Proved
Cot A - 1 + Cosec A / Cot A - Cosec A + 1
now putting 1= Cosec^2 - Cot ^2
= (Cot A + Cosec A) - (Cosec2 A - Cot2 A) / (Cot A - Cosec A + 1)
= (Cot A + Cosec A) [1 - Cosec A + Cot A) / (Cot A - Cosec A + 1)]
= (Cot A + Cosec A) RHS Proved