Practicing Success

Target Exam

CUET

Subject

General Test

Chapter

Numerical Ability

Topic

Average

Question:

If the average of x and \(\frac{1 }{x}\) \((x\neq 0)\) is M, then the average of \(x^{2} and \frac{1 }{x^{2}}\) is:

Options:

\(1-m^{2}\)

1 + 2m

\(2m^{2}-1\)

\(2m^{2}+1\)

Correct Answer:

\(2m^{2}-1\)

Explanation:

\(\frac{x + \frac{1}{×}}{2}\) = m

⇒ x + \(\frac{1}{×}\) = 2m

x2 + \(\frac{1}{×^2}\) = 4m2 - 2

Avg. = \(\frac{4m^2 - 2}{2}\) = 2m2 - 1