$${ \left(2x+4y \right) }^{ 8 }$$
$256\left(x+2y\right)^{8}$
$256x^{8}+458752x^{3}y^{5}+458752x^{2}y^{6}+262144xy^{7}+65536y^{8}+114688y^{3}x^{5}+28672y^{2}x^{6}+4096yx^{7}+286720\left(xy\right)^{4}$
