Practicing Success

Target Exam

CUET

Subject

General Test

Chapter

Quantitative Reasoning

Topic

Trigonometry

Question:

\(\frac{cos^2 θ}{cot^2 θ - cos^2 θ}\) = 3 and 0° < θ < 90° , then value of θ is?

Options:

30°

15°

60°

45°

Correct Answer:

60°

Explanation:

\(\frac{cos^2 θ}{cot^2 θ - cos^2 θ}\) = 3 ⇒ cos2 θ = 3(cot2 θ - cos2 θ)

⇒ 4cos2 θ = 3cot2 θ ⇒  4cos2 θ = \(\frac{3cos^2 θ}{sin^2 θ}\)

⇒ sin2 θ = \(\frac{3}{4}\) ⇒ sin θ = \(\frac{\sqrt {3 }}{2}\)

⇒ sin θ = \(\frac{\sqrt {3 }}{2}\) ⇒ θ = 60°