Question

(tan A)/(sec(A) - 1) + (tan A)/(sec(A) + 1) = 2cos ecA

Answer 1

Explanation:

LHS = tanθ/secθ - 1 + tanθ/secθ + 1

Cross multiplication,

tanθ(1 - secθ) - tanθ(1 + secθ)/1 + sec^2θ

= tanθ(1 - secθ - 1 - secθ)/-tan^2θ

= -2secθ/-tanθ

= 2 x 1/cosθ / sinθ/cosθ

= 2cosecθ = RHS

Hence proved.