Target Exam

CUET

Subject

General Test

Chapter

Quantitative Reasoning

Topic

Trigonometry

Question:

If secx = 7x and tanx =\(\frac{7}{x}\)

find the value of 98(x2-\(\frac{1}{x^2}\))+2.

Options:

7

4

0

6

Correct Answer:

4

Explanation:

We know that sec2x - tan2x = 1

(7x)2 - (\(\frac{7}{x}\))2=1

49x2 -\(\frac{49}{x^2}\) = 1

49(x2-\(\frac{1}{x^2}\)) = 1

x2-\(\frac{1}{x^2}\)=\(\frac{1}{49}\) ⇒ Put in find

⇒ 98(\(\frac{1}{49}\))+2

= 4