If $(x -\frac{1}{x})= 7.5$, what is the

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Target Exam

CUET

Subject

General Test

Chapter

Quantitative Reasoning

Topic

Algebra

Question:

If $(x -\frac{1}{x})= 7.5$, what is the value of $(x^2 + \frac{1}{x^2})$?

Options:

54.25

58.25

60.25

56.25

Correct Answer:

58.25

Explanation:

If $K-\frac{1}{K}=n$

then, $K^2+\frac{1}{K^2}$ = n² + 2 × k × $\frac{1}{k}$

If $(x -\frac{1}{x})= 7.5$

The value of $(x^2 + \frac{1}{x^2})$ = 7.5² + 2

= $(x^2 + \frac{1}{x^2})$ = 56.25 + 2 = 58.25