Question

$$x ^ { 8 } y ^ { 8 } + x ^ { 4 } y ^ { 4 } + 1$$

Evaluate

$\left(xy\right)^{8}+\left(xy\right)^{4}+1$

Differentiate w.r.t. x

$4x^{3}y^{4}\left(2\left(xy\right)^{4}+1\right)$