Спрости вираз 1) m3 + (4m3 - m2-9) + (8m3 + 9m2 - 6) = 2) -(xy + 3x3 - y2) - ( -4xy - 2x3...

Решите задачу:

$m {}^{3} + (4m {}^{3} - {m}^{2} - 9) + (8m {}^{3} - 9 {m}^{2} - 6) = \\ = m {}^{3} + 4m {}^{3} - {m}^{2} - 9+ 8m {}^{3} - 9 {m}^{2} - 6 = \\ = 13 {m}^{3} - 10 {m}^{2} - 15$

$- (xy + 3 {x}^{3} - {y}^{2} ) - ( - 4xy - 2 {x}^{3} + 7 {y}^{2} ) = \\ = - xy - 3 {x}^{3} + {y}^{2} + 4xy + 2 {x}^{3} - 7 {y}^{2} = \\ = 3xy - {x}^{3} - 6{y}^{2}$