Question

If 2x = sec A and `2/x = tan A` then `2(x^2 - 1/x^2)` = ?

Options

• `1/2`

• `1/4`

• `1/8`

• `1/16`

Answer 1

`bb(1/2)`

Explanation:

(sec²A – tan²A) = 1

⇒ `(4x^2 - 4/x^2) = 1`

⇒ `4(x^2 - 1/x^2) = 1`

∴ `2(x^2 - 1/x^2) = 1/2`.