Question

need the solutions urgent . please any genius solve it.

Answer 1

error in your question...between sin²@ and 2sin⁴@ it will be + sign,

L.H.S

sec²@ - [sin²@(1-2sin²@)]/[cos²@(2cos²@-1)],

sec²@ - [sin²@(cos2@)]/[cos²@(cos2@)],


sec²@ -sin²@/cos²@,

sec²@-tan²@,

1,

hence
L.H.S=R.H.S

since
(1-2sin²@)=cos2@,

(2cos²@-1)=cos2@,

sec²@-tan²@=1