13 Views

Question : If $\frac{\sqrt{38-5 \sqrt{3}}}{\sqrt{26+7 \sqrt{3}}}=\frac{a+b \sqrt{3}}{23}, b>0$, then the value of $(b-a)$ is:

Option 1: 7

Option 2: 18

Option 3: 29

Option 4: 11


Team Careers360 19th Jan, 2024
Answer (1)
Team Careers360 25th Jan, 2024

Correct Answer: 29


Solution : $\frac{\sqrt{38-5 \sqrt{3}}}{\sqrt{26+7 \sqrt{3}}}=\frac{a+b \sqrt{3}}{23}, b>0$
$⇒\frac{\sqrt{38-5 \sqrt{3}}}{\sqrt{26+7 \sqrt{3}}}=\frac{a+b \sqrt{3}}{23}$
$⇒\frac{\sqrt{(38-5 \sqrt{3)}({26-7 \sqrt{3}})}}{\sqrt{(26+7 \sqrt{3})({26-7 \sqrt{3}})}}=\frac{a+b \sqrt{3}}{23}$
$⇒\frac{\sqrt{(988+105-396\sqrt3)}}{\sqrt{(529)}}=\frac{a+b \sqrt{3}}{23}$
$⇒\frac{\sqrt{(11^2+(18\sqrt3)^2-2\times11\times18\sqrt3)}}{\sqrt{(23^2)}}=\frac{a+b \sqrt{3}}{23}$
$⇒\frac{\sqrt{(18\sqrt3-11)^2}}{23}=\frac{a+b \sqrt{3}}{23}$
$⇒\frac{(18\sqrt3-11)}{23}=\frac{a+b \sqrt{3}}{23}$
On comparing,
$a=-11$ and $b=18$
So, $(b-a)=18+11 = 29$
Hence, the correct answer is 29.

SSC CGL Complete Guide

Candidates can download this ebook to know all about SSC CGL.

Download EBook

Know More About

Related Questions

TOEFL ® Registrations 2024
Apply
Accepted by more than 11,000 universities in over 150 countries worldwide
Manipal Online M.Com Admissions
Apply
Apply for Online M.Com from Manipal University
GRE ® Registrations 2024
Apply
Apply for GRE® Test now & save 10% with ApplyShop Gift Card | World's most used Admission Test for Graduate & Professional Schools
View All Application Forms

Download the Careers360 App on your Android phone

Regular exam updates, QnA, Predictors, College Applications & E-books now on your Mobile

150M+ Students
30,000+ Colleges
500+ Exams
1500+ E-books