Question

Помогите пожалуйста(6,8,10)

Answer 1

6.
$= b^{2} ( \times 5b - 3) - b \times (3b - 2) = - b \times (b \times (5b - 3) + 3b - 2) = - b \times (5b ^{2} - 3b + 3b - 2) = - b ( - 5b ^{2} - 2)$