Practicing Success

Target Exam

CUET

Subject

General Test

Chapter

Quantitative Reasoning

Topic

Algebra

Question:

What is the Simplified value of:
$\frac{1}{8}\left\{\left(x + \frac{1}{y}\right)^2 - \left(x - \frac{1}{y}\right)^2\right\}$

Options:

$\frac{x}{y}$

$\frac{2x}{y}$

$\frac{x}{2y}$

$\frac{4x}{y}$

Correct Answer:

$\frac{x}{2y}$

Explanation:

$\frac{1}{8}\left\{\left(x + \frac{1}{y}\right)^2 - \left(x - \frac{1}{y}\right)^2\right\}$

Put the values of x and y = 1 and satisfy from the options.

$\frac{1}{8}\left\{\left(1 + \frac{1}{1}\right)^2 - \left(1 - \frac{1}{1}\right)^2\right\}$

= \(\frac{1}{8}\)[4-0] = \(\frac{1}{2}\)

If we choose option = $\frac{x}{2y}$ and put the values of x and y

= $\frac{1}{2(1)}$ = \(\frac{1}{2}\) satisfied.