Question

Sec4A-1/Sec2A+1=Tan4A/TanA​

Answer 1

Step-by-step explanation:

LHS

    sec4A -1 / sec2A-1  

 = 1/ cos4A - 1 / 1/cos2A -1

 =  (1- cos4A ) . cos2A /  cos4A (1- cos2A )

 =  2 sin2 2A . cos2A / cos4A . 2 sin2 A

 =  2 sin2A cos2A . sin2A / cos4A . 2sin2 A

 = sin4A . 2 sinA cosA / cos4A . 2 sin2 A

 =  tan4A / tanA = RHS