Question 74

If $$x^2 + \frac{1}{x^2} = 38$$, then what is the value of $$\mid x - \frac{1}{x} \mid$$?

Solution

$$x^2 + \frac{1}{x^2} = 38$$

$$=$$> $$x^2+\frac{1}{x^2}-2+2=38$$

$$=$$> $$x^2+\frac{1}{x^2}-2.x.\frac{1}{x}+2=38$$

$$=$$> $$\left(x-\frac{1}{x}\right)^2=38-2$$

$$=$$> $$\left(x-\frac{1}{x}\right)^2=36$$

$$=$$> $$\mid x - \frac{1}{x} \mid=6$$

Hence, the correct answer is Option C

Create a FREE account and get:

Free SSC Study Material - 18000 Questions
230+ SSC previous papers with solutions PDF
100+ SSC Online Tests for Free

CAT Quant Questions | CAT Quantitative Ability

CAT Quadratic Equations Questions CAT Averages, Ratio and Proportion Questions CAT Linear Equations Questions CAT Functions, Graphs and Statistics Questions CAT Inequalities Questions

CAT DILR Questions | LRDI Questions For CAT

CAT 2D & 3D LR Questions CAT Charts Questions CAT Data change over a period Questions CAT Puzzles Questions CAT DI Miscellaneous Questions

CAT Verbal Ability Questions | VARC Questions For CAT

CAT Verbal Ability Questions CAT Para Jumbles Questions CAT Odd One Out Questions CAT Vocabulary Questions CAT Grammar and Sentence Correction Questions

Follow us on

Boost your Prep!

Download App