Practicing Success

Target Exam

CUET

Subject

General Test

Chapter

Quantitative Reasoning

Topic

Trigonometry

Question:

If $4(cosec^2 57°-tan^2 33°) - cos 90°- y tan^2 66° tan^2 24°=\frac{y}{2}$, the value of y is:

Options:

$\frac{8}{3}$

$\frac{3}{8}$

8

$\frac{1}{3}$

Correct Answer:

$\frac{8}{3}$

Explanation:

4(cosec²57º - tan²33º) - cos90º - y tan²66º . tan²24º = \(\frac{y}{2}\)

{ using , Iff A + B = 90º , then  tanA = cotB }

4(cosec²57º - cot²57º) - cos90º - y tan²66º . cot²66º = \(\frac{y}{2}\)

{ we know, cosec²A - cot²A = 1 and tanA = \(\frac{1}{cotA}\) }

4(1) - 0 - y  = \(\frac{y}{2}\)

4 = y + \(\frac{y}{2}\)

4 = \(\frac{3y}{2}\)

y = \(\frac{8}{3}\)