Question

plz help me in getting the answer

Answer 1

a3+b3+c3 -3abc = (a+b+c) ( a^2 +b^2+ c^2- ab-bc-ca)
Now as a+b+c= 0
therefore
a^3+b^3 + c^3 - 3abc = 0 ( a^2+b^2+c^2-ab-bc-ca)
a3+b3+c3 -3abc = 0
a3+b3+c3 =3abc

Answer 2

a +b+c =0
Or, a+b = - c
Or, (a+b) ³ = (-c) ³...cubing both sides..
Or, a³+b³ +3ab(a+b) = - c³
Or, a³+b³+ 3ab(-c)+c³=0
Or, a³+b³+c³= 3abc.. [proved]