Question

if a²+b²+c²=20 and a+b+c =0, find ab+bc+ca​

Answer 1

Answer:

Step-by-step explanation:

(a+b+c)² = a² + b² + c² + 2(ab + bc + ca)

So,

(0)² = 20 + 2(ab + bc + ca)

=> 0 = 20 + 2(ab + bc + ca)

=> -20 = 2(ab + bc + ca)

=> -20/2 = (ab + bc + ca)

=> -10 = (ab + bc + ca)

Hence,

ab+ bc+ca = -10

(THIS IS COPIED please go to https://brainly.in/question/3957013 to thanks the guy who wrote this , i don't deserve this :D )