(sec square theta – 1) (1 – cosec square Theta) = -1

(sec^2 theta-1) (1-cosec^2 theta)= -1

Q. sec2-11-cosec2= -1

Sol. LHS = sec2-11-cosec2

1+tan2-11-1+cot2 by using sec2=(1+tan2) and cosec2=(1+cot2)

tan2.(-cot2)

tan2.-1tan2

-1=RHS