If 2sin2θ + 3cosθ = 3, 0° < θ < 90°, then the value of (sec2θ + cot2θ) is:
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Correct answer: C
Explanation
The correct answer is option 3 i.e. 4![]()
Calculations:
We know that sin2θ = 1 - cos2θ
⇒ 2sin2θ + 3cosθ = 3
2(1 - cos2θ) + 3cosθ = 3
Take cosθ = a
⇒ 2 - 2a2 + 3a = 3
⇒ 2a2 - 3a + 1 = 0
⇒ (2a - 1) (a - 1) = 0
⇒ a = 1/2, 1
⇒ cosθ = 1/2, 1 i.e. θ = 60°
Putting the value of θ, we get
⇒ sec260 + cot260 = 4 + 1/3 =