Question

. If x = 3 sec²0-1, y = tan²0 – 2 then find x - 3y.

Answer 1

x-3y=-4

1. x-3y=3Sec²θ-1-3*(tan²θ-2)

x-3y=3Sec²θ-1-3tan²θ-6

x-3y=3*(Sec²θ-tan²θ)-7

x-3y=3*1-7       [Sec²θ-tan²θ=1]

x-3y=-4