`sec^2 A(1+sec2A) = 2sec2A`

(sec 2A+1 ) sec ^(2) A= ................. A) sec A B) 2 sec A C) sec 2A D) 2 sec 2A

If angle A and angle B are complementary to each other,then the value of sec^2 A + sec^2 B - sec^2 A sec^2 B is

(sec2A+1)sec^2A=

sec^2 A+ sec^2(\pi /2- A) = sec^2A sec^2(\pi/2 -A)

Prove that (1+sec2A)(1+sec2^2A)(1+sec2^3A).....(1+sec2^nA)=(tan2^nA)/(tanA)

((sin2A)/(sec A-1))((sec2A)/(sec2A+1))=

((sin 2A)/(sec A -1))((sec 2A)/(sec 2A+1))=

sec^(2)A sec^(2)B-sec^(2)A tan^(2)B-tan^(2)A sec^(2)B+tan^(2)A tan^(2)B=

(sec 2A+1 ) sec ^(2) A=

sec^4 A - sec^2 A =……….