Question

5 tan² A – 5 sec² A + 1 is equal to

Comments

5 tan^2 A - 5sec^2 A + sec^2 A - tan^2 A   [sec^2 A - tan^2 A = 1]
= 4tan^2 A - 4sec^2 A
= -4 ( sec^2 A - tan^2 A)
= -4(1)                          [sec^2 A - tan^2 A = 1]
=-4 (Answer)

Answer 1

5 tan² A - 5 sec² A + 1

= 5(tan² A - sec² A) + 1

= 5(-1) + 1   [∵ sec² A + tan² A = 1, tan² A - sec² A = -1]

= -5 + 1

= -4