Question : If $a+b+c=0$, the value of $\frac{a^2+b^2+c^2}{a^2-bc}$ is:
Option 1: 0
Option 2: 1
Option 3: 2
Option 4: 3
Latest: SSC CGL preparation tips to crack the exam
Don't Miss: SSC CGL complete guide
Correct Answer: 2
Solution :
Given:
$a+b+c=0$
$\therefore b+c=-a$
Now, $a+b+c=0$
By squaring both sides, we get,
$(a+b+c)^2=0$
⇒ $a^2+b^2+c^2+2(ab+bc+ca)=0$
⇒ $a^2+b^2+c^2+2[a(b+c)+bc]=0$
⇒ $a^2+b^2+c^2+2[a(-a)+bc]=0$
⇒ $a^2+b^2+c^2-2[a^2-bc]=0$
⇒ $a^2+b^2+c^2=2[a^2-bc]$
$\therefore\frac{a^2+b^2+c^2}{a^2-bc}=2$
Hence, the correct answer is $2$.
Related Questions
Know More about
Staff Selection Commission Combined Grad ...
Answer Key | Eligibility | Application | Selection Process | Preparation Tips | Result | Admit Card
Get Updates Brochure
Your Staff Selection Commission Combined Graduate Level Exam brochure has been successfully mailed to your registered email id “”.
