Question : If $a+\frac{1}{a}=8$, then what is the value of $\frac{1}{a^4}+a^4 ?$
Option 1: 4098
Option 2: 3846
Option 3: 3842
Option 4: 4094
Recommended: How to crack SSC CHSL | SSC CHSL exam guide
Don't Miss: Month-wise Current Affairs | Upcoming government exams
New: Unlock 10% OFF on PTE Academic. Use Code: 'C360SPL10'
Correct Answer: 3842
Solution : $(a + \frac{1}{a}) = 8$ Squaring both sides, we get, ⇒ $ (a^2 + \frac{1}{a^2}) + 2 = 64$ ⇒ $(a^2 + \frac{1}{a^2}) = 62$ Squaring both sides again, we get, ⇒ $a^4 + \frac{1}{a^4} + 2 = 3844$ ⇒ $a^4 + \frac{1}{a^4} = 3844 - 2$ ⇒ $a^4 + \frac{1}{a^4} = 3842$ Hence, the correct answer is 3842.
Candidates can download this e-book to give a boost to thier preparation.
Application | Eligibility | Admit Card | Answer Key | Preparation Tips | Result | Cutoff
Question : If $a+\frac{1}{a}=2$ and $b+\frac{1}{b}=-2$, then what is the value of $a^2+\frac{1}{a^2}+b^2+\frac{1}{b^2} ?$
Option 1: 0
Option 2: 2
Option 3: 8
Option 4: 4
Question : If $a^2+\frac{1}{a^2}=\frac{7}{3}$, then what is the value of $\left(a^3-\frac{1}{a^3}\right)?$
Option 1: $\frac{5}{3 \sqrt{3}}$
Option 2: $\frac{10}{3 \sqrt{3}}$
Option 3: $\frac{7}{3 \sqrt{3}}$
Option 4: $\frac{8}{3 \sqrt{3}}$
Question : If $\sec A=\frac{17}{15}$, then what is the value of $\cot A$?
Option 1: $\frac{15}{21}$
Option 2: $\frac{15}{7}$
Option 3: $\frac{8}{15}$
Option 4: $\frac{15}{8}$
Question : Find the value of the given expression: $\frac{(4\frac{1}{3}+3\frac{1}{3}\times 1\frac{4}{5}\div 3\frac{3}{4}\times (1\frac{1}{2}+1\frac{1}{3}))}{(\frac{2}{3}\div \frac{5}{6}\times \frac{2}{3})}$
Option 1: $11 \frac{3}{8}$
Option 2: $10\frac{1}{8}$
Option 3: $14\frac{3}{8}$
Option 4: $16\frac{5}{8}$
Question : If $2 x+\frac{2}{x}=5$, then the value of $\left(x^3+\frac{1}{x^3}+2\right)$ will be:
Option 1: $\frac{81}{11}$
Option 2: $\frac{81}{7}$
Option 3: $\frac{71}{8}$
Option 4: $\frac{81}{8}$
Regular exam updates, QnA, Predictors, College Applications & E-books now on your Mobile