Which of the following fractions is equal to 1 √ 5 − √ 7 ? Options: A . &nbsp − ( √ 5 + √ 7 ) 4 B . &nbsp − ( √ 5 + √ 7 ) 2 C . &nbsp − ( √ 5 − √ 7 ) 2 D . &nbsp − ( √ 5 + √ 7 ) 8

Answer: Option B : B Rationalizing the expression we get, 1 √ 5 − √ 7 = √ 5 + √ 7 ( √ 5 − √ 7 ) ( √ 5 + √ 7 ) = √ 5 + √ 7 ( √ 5 ) 2 − ( √ 7 ) 2 = √ 5 + √ 7 5 − 7 = − ( √ 5 + √ 7 ) 2

Which of the following fractions is equal to 1√5−√7?

Question

Which of the following fractions is equal to $\frac{1}{\sqrt{5} - \sqrt{7}}$ ?

Options:

A .

\frac{- (\sqrt{5} + \sqrt{7})}{4}

B .

\frac{- (\sqrt{5} + \sqrt{7})}{2}

C .

\frac{- (\sqrt{5} - \sqrt{7})}{2}

D .

\frac{- (\sqrt{5} + \sqrt{7})}{8}

Answer: Option B
:
B

Rationalizing the expression we get,
$\frac{1}{\sqrt{5} - \sqrt{7}} = \frac{\sqrt{5} + \sqrt{7}}{(\sqrt{5} - \sqrt{7}) (\sqrt{5} + \sqrt{7)}}$

= $\frac{\sqrt{5} + \sqrt{7}}{(\sqrt{5})^{2} - (\sqrt{7})^{2}}$

= $\frac{\sqrt{5} + \sqrt{7}}{5 - 7}$
= $\frac{- (\sqrt{5} + \sqrt{7})}{2}$

Was this answer helpful ?

Next Question

Submit Solution

More Questions on This Topic :

Question 1. n√2×n√3=n√6 ....

Question 2. Convert hexadecimal value 16 to decimal.....

Question 3. Convert the following decimal number to 8-bit binary. 187....

Question 4. Convert the following binary number to decimal. 010112....

Question 5. Decode the following ASCII message. 10100111010100101010110001001011001 01000001001000100000110100101000100....

Question 6. One hex digit is sometimes referred to as a(n):....

Question 7. Convert the binary number 1001.00102 to decimal.....

Question 8. Convert binary 111111110010 to hexadecimal.....

Question 9. Which of the following is the most widely used alphanumeric code for computer input and output?....

Question 10. If a typical PC uses a 20-bit address code, how much memory can the CPU address?....

Chapter 1 - GLOBAL STEEL SCENARIO & INDIAN STEEL INDUSTRY Part 1 : (13-04-2024) INDUSTRY AND COMPANY AWARENESS (ICA)

Direction Sense Test Part 1 Reasoning (Hindi)

Chapter 1 - RMHP / OHP / OB & BP Part 1 : (14-02-2024) GPOE

Cube & Cuboid Part 1 Reasoning (Hindi)

Data Interpretation (DI) Basic Concept Reasoning (Hindi)

Counting Figures Part 1 Counting Of Straight Lines Reasoning (Hindi)

Sail E0 free webinar Webinars

Real Numbers Part 7 Class 10 Maths

Real Numbers Part 1 Class 10 Maths

Polynomials Part 1 Class 10 Maths

GPOE / GPA Combined 1 Free Mock Test SAIL JO E-0 2024

Chapter 3.1 : INTRODUCTION Chapter 3 : Sinter Plant SAIL E0 - GPOE/GPA 2024

Chapter 2.3 : COAL HANDLING PLANT - Set 1 Chapter 2 : Coke Ovens and Coal Chemicals SAIL E0 - GPOE/GPA 2024

Chapter 1.1 : INTRODUCTION Chapter 1 : Raw Material Handling Plant SAIL E0 - GPOE/GPA 2024

DSP Combined 1 Free Revision Test SAIL JO E-0

Submit Solution

More Questions on This Topic :

Latest Videos

Latest Test Papers