1 View

Question : if $x+\frac{1}{x}=2$, then the value of $x^4+\frac{1}{x^4}$=__________.

Option 1: 0

Option 2: 2

Option 3: –1

Option 4: 1


Team Careers360 8th Jan, 2024
Answer (1)
Team Careers360 21st Jan, 2024

Correct Answer: 2


Solution : Given: $x+\frac{1}{x}=2$
Squaring both sides, we get
⇒ $(x+\frac{1}{x})^2=2^2$
⇒ $x^2+\frac{1}{x^2}+2\times x\times\frac{1}{x}=4$
⇒ $x^2+\frac{1}{x^2}=4-2$
⇒ $x^2+\frac{1}{x^2}=2$
Again squaring both sides, we get:
⇒ $(x^2+\frac{1}{x^2})^2=2^2$
⇒ $x^4+\frac{1}{x^4}+2\times x^2\times\frac{1}{x^2}=4$
⇒ $x^4+\frac{1}{x^4}=4-2$
⇒ $x^4+\frac{1}{x^4}=2$
Hence, the correct answer is 2.

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