Question : If $\frac{a}{b}+\frac{b}{a}=-1$ and $a-b=2$, then the value of $a^3-b^3$ is:
Option 1: $0$
Option 2: $\frac{1}{2}$
Option 3: $1$
Option 4: $–1$
Latest: SSC CGL preparation tips to crack the exam
Don't Miss: SSC CGL complete guide
New: Unlock 10% OFF on PTE Academic. Use Code: 'C360SPL10'
Correct Answer: $0$
Solution : $\frac{a}{b}+\frac{b}{a}=-1$ ⇒ $a^2 + b^2 + ab = 0$ Also, $a-b=2$ ⇒ $a^3-b^3 = (a−b)(a^2+b^2+ab) = -2\times 0 = 0$ Hence, the correct answer is $0$.
Candidates can download this ebook to know all about SSC CGL.
Answer Key | Eligibility | Application | Selection Process | Preparation Tips | Result | Admit Card
Question : If $(a+\frac{1}{a})=–2$, then the value of $a^{1000}+a^{–1000}$ is:
Question : If $a+\frac{1}{a}=1$, then the value of $\frac{a^2-a+1}{a^2+a+1}$ is $(a\neq 0)$:
Question : If $\frac{a}{b}+\frac{b}{a}=1$, then the value of $(a^3+b^3)$ is:
Question : If $a+\frac{1}{a-2}=4$, then the value of $(a-2)^{2}+(\frac{1}{a-2})^{2}$ is:
Question : If $a+b=2c$, then the value of $\frac{a}{a–c}+\frac{c}{b–c}$ is equal to (where $a\neq b\neq c$):
Regular exam updates, QnA, Predictors, College Applications & E-books now on your Mobile