Practicing Success

Target Exam

CUET

Subject

General Test

Chapter

Quantitative Reasoning

Topic

Trigonometry

Question:

The value of $\frac{3tan^260°+sec^230°-sin^245°}{(cos15°+sin75°)(sec15°+cosec75°)}$ is :

Options:

$\frac{5}{12}$

$\frac{65}{24}$

$\frac{13}{12}$

$\frac{59}{24}$

Correct Answer:

$\frac{59}{24}$

Explanation:

$\frac{3tan^260°+sec^230°-sin^245°}{(cos15°+sin75°)(sec15°+cosec75°)}$

{ using , sinA = cos ( 90° - A ) }

= $\frac{3 ×(√3)²+(2/√3)² - (1/√2)²}{(cos15°+cos15°)(sec15°+sec15°)}$

= $\frac{9+4/3 - 1/2}{(2cos15°)(2sec15°)}$

= $\frac{(54+8 - 3 )}{6}$

= $\frac{(59 )}{24}$