{(1/cosθ) + (1/cotθ)} {(1/cosθ) - (1/cotθ)} এর মান কত?

A 1/2

B -1

C 1

Correct Answer: Option C

{(1/cosθ) + (1/cotθ)} {(1/cosθ) - (1/cotθ)}
= (secθ + tanθ) (secθ - tanθ)
= sec²θ - tan²θ [যেহেতু, 1 + tan²θ = sec²θ]
= 1