Question

Prove the trig identity: (tanx/1+secx)+(1+secx/tanx)=2cscx

Answer 1

=[(sinx/cosx)/(1+1/cosx)] + [(1+1/cosx)/(sinx/cosx)]

=[(sinx/cosx)/(cosx+1/cosx)]+[(cosx+1/cosx)/(sinx/cosx)]

= [sinx/(cosx+1)] + [(cosx+1)/sinx]

= [sin^2x+(cosx+1)^2] / [sinx (cosx+1)]

= [2+2cosx] / [sinx(cosx+1)]

=[2(cosx+1)] / [sinx (cosx+1)]

= 2/sinx

= 2 cscx

(I think this will be helpful for you. if you can see the picture, it has more detail in it.)