Question

Question #71bbb

Answer 1

`LHS=2sec^2 x - 2sec ^2 x sin^2 x - cos ^2 x`

`=2sec^2 x(1 - sin^2 ) - cos ^2 x`

`=2sec^2 x cos^2x - cos ^2 x`

`=2 - cos ^2 x =1+(1-cos^2x)`

`=1+sin^2x!=RHS`