If a+b+c=5 and ab+bc+ca=10 then find the value of a^3+b^3+c^3-3abc

1.	If a+b+c=5 and ab+bc+ca=10 then find the value of a^3+b^3+c^3-3abc
Answer» (a+b+c)2=a2+b2+c2+2(ab+bc+ca)a2+b2+c2=52-2×10=5So A3+b3+c3-3abc=(a+b+c)(a2+b2+c2-ab-bc-ca)=(5)(5-10)= -25

Discussion