Question

For θ > π/3, the value of f(θ) = sec² θ + cos²θ  always lies in the interval 

(A)  (0, 2)

(B)  (0, 1)

(C)  (1, 2)

(D)  [2, ∞)

Answer 1

Correct option  (D) [2, ∞)

Explanation :

Here, 

 Therefore, the required interval is [2, ∞).