Practicing Success

Target Exam

CUET

Subject

General Test

Chapter

Quantitative Reasoning

Topic

Trigonometry

Question:

If cosec θ + cot θ = 3 ; what is the value of cosecθ.cotθ ?

Options:

1

 \(\frac{3}{4}\)

 \(\frac{20}{9}\)

 \(\frac{22}{9}\)

Correct Answer:

 \(\frac{20}{9}\)

Explanation:

cosec θ + cot θ = 3

⇒ cosec θ - cot θ = \(\frac{1}{3}\)

4cosecθ.cotθ = (cosecθ + cotθ)2 - (cosecθ - cotθ)2

⇒ 4cosecθ.cotθ = 32 - \(\frac{1}{3^2}\)

⇒ cosecθ.cotθ = \(\frac{1}{4}\)(9 -  \(\frac{1}{9}\))\(\frac{80}{36}\) = \(\frac{20}{9}\)