10C5{ }^{10} \mathrm{C}_{5}10C5
10C6{ }^{10} \mathrm{C}_{6}10C6
10C6(yx)2{ }^{10} C_{6}\left(\frac{y}{x}\right)^{2}10C6(xy)2
10C5(yx)5{ }^{10} C_{5}\left(\frac{y}{x}\right)^{5}10C5(xy)5