Practicing Success

Target Exam

CUET

Subject

General Test

Chapter

Quantitative Reasoning

Topic

Trigonometry

Question:

If 48 sin4 ∝ + 80 cos4 ∝ = 30, then 54 tan6 ∝ + 125 cosec6 ∝ = ?

Options:

712

762

718

772

Correct Answer:

762

Explanation:

\(\frac{48}{30}\) sin4 ∝ + \(\frac{80}{30}\) cos4 ∝ = 1

( \(\frac{8}{5}\)sin2 ∝) . sin2 ∝ + ( \(\frac{8}{3}\)cos2 ∝) . cos2 ∝ - 1

we know 1. sin2 ∝ + cos2 ∝ = 1

so, \(\frac{8}{5}\)sin2 ∝ = 1               cos2 ∝ = \(\frac{3}{8}\) = tan2 ∝ = \(\frac{5}{3}\)

sin2 ∝ = \(\frac{5}{8}\)

54tan6 ∝+ 125 cosec6 ∝ = 54 × (\(\frac{125}{27}\)) + 125 (\(\frac{512}{125}\)) = 250 + 512 = 762