Practicing Success

Target Exam

CUET

Subject

General Test

Chapter

Quantitative Reasoning

Topic

Trigonometry

Question:

If cosec θ + cot θ = 2, then sin θ is :

Options:

$\frac{3}{5}$

$\frac{2}{5}$

$\frac{3}{4}$

$\frac{4}{5}$

Correct Answer:

$\frac{4}{5}$

Explanation:

cosec θ + cot θ = 2      -----(1)

{ we know, cosec²θ - cot²θ = 1 }

so, cosec θ -  cot θ = \(\frac{1 }{cosec θ + cot θ}\)

⇒ cosec θ -  cot θ = \(\frac{1 }{2}\)     -----(2)

Adding equation 1 and 2.

2 cosec θ  = 2 + \(\frac{1 }{2}\) = \(\frac{5 }{2}\)

cosec θ = \(\frac{5 }{4}\)

{ we know,  sin θ = \(\frac{1 }{cosec θ}\) }

so, sin θ = \(\frac{4 }{5}\)