Practicing Success

Target Exam

CUET

Subject

General Test

Chapter

Quantitative Reasoning

Topic

Trigonometry

Question:

Find the value of $\frac{cos^230°-sin^230°}{sin^215°+cos^215°}$.

Options:

$\frac{1}{2}$

1

$1-\sqrt{3}$

0

Correct Answer:

$\frac{1}{2}$

Explanation:

\(\frac{cos²30º - sin²30º }{sin²15º + cos²15º}\)

{ we know, sin²A + cos²A = 1  ,  cos30º = \(\frac{√3}{2}\) & sin30º = \(\frac{1}{2}\) }

= \(\frac{(√3/2)² - (1/2)² }{1}\)

= \(\frac{3 }{4}\) - \(\frac{1 }{4}\)

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