Question

If
A+b+C = 12 and a² +b² + c²=64
then find the value of (ab +bc + CA)​

Answer 1

40

Step-by-step explanation:

we know that (a+b+c)^2=a^2+b^2+c^2+2(ab+bc+ca)

hare (a+b+c)=12 so,(a+b+c)^2=12^2=144

given a^2+b^2+c^2=64 so 2(ab+bc+ca)=144-64=80

so, (ab+bc+ca)=40