Hai sa notam elementul neutru cu e.
[tex]x\circ e=e\circ x=x\\x\circ e=x\\xe+\hat{5} x+\hat5 e+\hat{6}=x\\e(x+\hat 5)=\hat3 x+\hat 1\\e=\dfrac{ \hat3 x+\hat 1}{x+\hat 5}=\dfrac{\hat 3(x+\hat 5)}{x+\hat 5}=\hat 3\\\text{Deci elementul neutru este }\hat 3.[/tex]
