Question

1-sin2α/cos2α=1-tanα/1+tanα​

Answer 1

Answer:

(1 - tanα) / (1 + tanα)

Step-by-step explanation:

sin(2α) =2tanα/(1+tan^2α)..........................(1)

cos(2α)=(1-tan^2α)/(1+tan^2α)   ...............(2)

RHS:-

=(1-sin2α)/cos2α

= 1- [2tanα/(1+tan^2α) ]  / { (1-tan^2α)/(1+tan^2α) }

taking LCM,

(1+ tan^2α -  2tanα) / (1 - tan^2α)

[ (1 - tanα)^2 ] / [ (1 - tanα)(1 + tanα)]

(1 - tanα) / (1 + tanα)......................................=>LHS