Question

√(1+cosα)/(1-cosα) + √(1-cosα)/(1+cosα) (180°

Answer 1

√[(1-cosα)/(1+cosα)]+√[(1+cosα)/(1-cosα)]

=√[(1-cosα)^2/(1+cosα)(1-cosα)]+√[(1+cosα)^2/(1-cosα)(1+cosα)]

=√[(1-cosα)^2/(sinα)^2]+√[(1+cosα)^2/(sinα)^2]

∵180°