Question

nếu a3+b3+c3=3abc thì a+b+c=...

Answer 1

a+b+c=abc?? =))

Answer 2

\(a^3+b^3+c^3=3abc\\ \Rightarrow\left(a+b+c\right)\left(a^2+b^2+c^2-ab-bc-ca\right)+3abc=3abc\\ \Rightarrow\left(a+b+c\right)\left(a^2+b^2+c^2-ab-bc-ca\right)=0\\ \Rightarrow\left[{}\begin{matrix}a+b+c=0\\a^2+b^2+c^2-ab-bc-ca=0\left(vô.lí\right)\end{matrix}\right.\)

Vậy a+b+c=0