Practicing Success

Target Exam

CUET

Subject

General Test

Chapter

Quantitative Reasoning

Topic

Algebra

Question:

If $x-\frac{1}{x}=11$, then $x^3-\frac{1}{x^3}$ is:

Options:

1474

1364

1188

1298

Correct Answer:

1298

Explanation:

If x + \(\frac{1}{x}\)  = n

then, $x^3 +\frac{1}{x^3}$ = n3 - 3 × n

If $x-\frac{1}{x}=11$

then $x^3-\frac{1}{x^3}$ = 113 - 3 × 11

$x^3-\frac{1}{x^3}$ =1331 - 33 = 1298