Question

помогите пожалуйста ​

Answer 1

$\displaystyle (\frac{1}{8}y^3-\frac{5}{6})^2=(\frac{1}{8}y^3)^2-2*\frac{1}{8}y^3*\frac{5}{6}+(\frac{5}{6})^2=\frac{1}{64}y^6-\frac{5}{24}y^3+\frac{25}{36}$