الف) $\frac{1}{2}x - 3y + 7 - [\frac{3}{2}x - 3y + 11] =$

ب) $\frac{3}{7}x - \frac{2}{7}y - \frac{2}{5}x + \frac{2}{5}y =$

ج) $(x - y) - (y - x) =$

د) $-\frac{1}{3x}(xy - x^2) + \frac{y}{2x} - \frac{1}{3} =$

ه) $8x^3 - 2(x - 1)(x^2 + x + 1) =$

و) $x - \frac{3x}{2}(2y - 2) - \frac{y}{3}(3x - 6 + 5y) =$