Answer
$20 a^{(3/2)} b^{(3/2)} + 6 a^{(5/2)}\sqrt(b) + a^3 + 15 a^2 b + 6 \sqrt(a) b^{(5/2)} + 15 a b^2 + b^3$
Work Step by Step
The coefficients of the polynomial expression will simply be the pascal's triangle number row corresponding to the power. Also the power's of x will start with the power and go down. The constant or y term will go up starting with to the power 0. Also if there is a coefficient of either term (like 4x instead of x) simply consider the coefficient as part of the whole term and expand afterwards
