Question

1/1+cosA. +. 1/1-cosA = 2cosec²A

Answer 1

Step-by-step explanation:

LHS=

1/1+cosa+1/1- cosa

1-cosa+1+cosa/(1+cosa)(1-cosa)

2/ (1-cosa)² {use identity sin²a+cos²a=1}

2/sin a² {here 1/sin²a=cosec²a}

2 cosec ²