Home PDF Store Exams G.K. Aptitude Reasoning English Computer Biology Privacy About Contact

$I f x = 3 + 2 \sqrt{2}, t h e n t h e v a l u e o f \sqrt{x} - \frac{1}{\sqrt{x}} i s :$

A. 1

B. 2

C. $2 \sqrt{2}$

D. $3 \sqrt{3}$

Correct Answer :

B. 2

{(\sqrt{x} - \frac{1}{\sqrt{x}})}^{2} = x + \frac{1}{x} - 2

= (3 + 2 \sqrt{2}) + \frac{1}{(3 + 2 \sqrt{2})} - 2

= (3 + 2 \sqrt{2}) + \frac{1}{(3 + 2 \sqrt{2})} \times \frac{(3 - 2 \sqrt{2})}{(3 - 2 \sqrt{2})} - 2

= (3 + 2 \sqrt{2}) + (3 - 2 \sqrt{2}) - 2

= 4.

∴ (\sqrt{x} - \frac{1}{\sqrt{x}}) = 2 .

Share this question with your friends

Show all Surds and Indices MCQ

Comment

Related Questions

(256)0.16 × (256)0.09 = ? If m and n are whole numbers such that mn = 121, the value of (m - 1)n + 1 is: (0.04)-1.5 = ? 243)n5 × 32n + 1 9n × 3n − 1… xbxc (b + c - a) . xcxa (c + a - b)… 11 + x(b - a) + x(c - a) … The value of [(10)150 ÷ (10)146] 11 + a(n - m) + 11 + a(m - n)… (25)7.5 × (5)2.5 ÷ (125)1.5 = 5? If x = 3 + 22, then the value of…

Also checkout

Fill in the blanks MCQ True Discount MCQ PageMaker MCQ Urinary incontinence MCQ Astronomy MCQ Chemical Process MCQ Machine Design MCQ Rearrangement Set 2 MCQ ionic Equilibrium MCQ Microsoft Word MCQ English Literature MCQ Decision Making MCQ