Question

If a+b+c=0 and ab+bc+ca=40, find a^2+b^2+c^2

Answer 1

Answer:

-80

Step-by-step explanation:

We know that the tes given can be compared to the identity which says that

-(a+b+c) ^2=a^2+b^2+c^2+2(ab+bc+ca)

Since, a+b+c=0 and

ab+bc+can=40

Therefore : (0)^2=a^2+b^2+c^2+2(40)

{I have inserted 0 and 40 bcoz it is mentioned that a+b+c=0 and ab + bc+ ca=40}

=> 0 =a^2+b^2+c^2+80

=> 0-80=a^2+b^2+c^2

=> -80=a^2+b^2+c^2

Answer is -80