Practicing Success

Target Exam

CUET

Subject

General Test

Chapter

Quantitative Reasoning

Topic

Algebra

Question:

If $(x + \frac{1}{x}) = 8.5$, what is the value of $(x^2 + \frac{1}{x^2})$ ?

Options:

70.25

74.25

72.25

75.25

Correct Answer:

70.25

Explanation:

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

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

If $(x + \frac{1}{x}) = 8.5$

$(x^2 + \frac{1}{x^2})$ = (8.5)2 – 2

$(x^2 + \frac{1}{x^2})$ = 72.25 - 2 = 70.25