−16+16+0=0−13+13+0=0−12+12+0=0−16−13+12=016+13−12=0
$
(-\frac{1}{6}
)+\frac{1}{6}+0=0$$
(-\frac{1}{3}
)+\frac{1}{3}+0=0$$
(-\frac{1}{2}
)+\frac{1}{2}+0=0$$
(-\frac{1}{6}
)+(-\frac{1}{3}
)+\frac{1}{2}=0$$\frac{1}{6}+\frac{1}{3}
+(-\frac{1}{2}
)=0$