\(\left(x+y\right)^5=x^5+y^5\)
\(\Leftrightarrow5xy\left(x+y\right)\left(x^2+xy+y^2\right)=0\)
\(\Leftrightarrow x=-y\)
Ta có :
\(\left(x+y\right)^5=x^5+y^5\)
\(\Leftrightarrow5\times xy\left(x+y\right)\left(x^2+xy+y^2\right)=0\)
\(\Leftrightarrow x=-y\)
\(\LeftrightarrowĐPCM\)