Question

(sec²60°– 1) = ?
(a) 0
(b) 2
(c) 3
(d) 4

Answer 1

As we know that,
$$\begin{gathered} \sec 60°=2 \\ \mathrm{By}\mathrm{substituting}\mathrm{the}\mathrm{value},\mathrm{we}\mathrm{get} \\ \left({\sec }^{2}60°-1\right)={\left(2\right)}^2-1 \\ =4-1 \\ =3 \\ \mathrm{Hence},\mathrm{the}\mathrm{correct}\mathrm{option}\mathrm{is}\left(\mathrm{c}\right). \end{gathered}$$