Practicing Success

Target Exam

CUET

Subject

General Test

Chapter

Quantitative Reasoning

Topic

Trigonometry

Question:

If 6 tan2θ - 2 = 0, find the value of 3sinθ + cos2(1.5θ)

Options:

7

\(\frac{7}{2}\)

4

2

Correct Answer:

2

Explanation:

6 tan2θ - 2 = 0

tan2θ = \(\frac{2}{6}\) = \(\frac{1}{3}\)

tanθ = \(\frac{1}{\sqrt {3}}\)

θ = 30°

Now,

⇒ 3sinθ + cos2(1.5θ) = 3 × \(\frac{1}{2}\) + cos2(45°)

= \(\frac{3}{2}\) + \(\frac{1}{2}\)  = 2