Question

If a + b + C = 9 and ab +bc+ca = 40 then find the value of a^3+b^3+c^3-3abc

Answer 1

Here is your solution

Answer 2

We Know that....

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

so by putting the values...

9^2=a^2+b^2+c^2+40

or ...

a^2+b^2+c^2=81-40

=41