Question

не удаляйте пж.Помогите срочно есть 30 минут до здачи домашнего задания​

Answer 1

1.=ab-3a+2b-2•3=ab-3a+2b-6
2.=m•m+5m-4m-4•5=m^2+5m-4m-20=m^2+m-20
3.3x•2x+3x•5-2x-5=6x^2+15x-2x-5=6x^2+13x-5

Answer 2

Объяснение:

1.

$(a + 2)(b - 3) = ab - 3a + 2b - 6$

2.

$(m - 4)(m + 5) = m \times m + 5m - 4m - 4 \times 5 = m {}^{2} + m - 20$

3.

$(3x - 1)(2x + 5) = 3x \times 2x + 3x \times 5 - 2x - 5 = 6x {}^{2} + 13x - 5$

4.

$(3b {}^{2} + 2)(2b - 4) = 3b {}^{2} \times 2b - 3b {}^{2} \times 4 + 2 \times 2b - 2 \times 4 = 6b {}^{3} - 12b {}^{2} + 4b - 8$

5.

$(4x - y)(2x - 3y) = 4x \times 2x - 4x \times 3y - 2xy - y \times ( - 3y) = 8x {}^{2} - 12xy - 2xy + 3y {}^{2} = 8x {}^{2} - 14xy + 3y {}^{2}$

6.

$(3a {}^{2} + a)(5a {}^{2} - 2a) = 3a {}^{2} \times 5a {}^{2} - 3a {}^{2} \times 2a + a \times 5a {}^{2} - a \times 2a = 15a {}^{4} - 6a {}^{3} + 5a {}^{3} - 2a {}^{2} = 15a {}^{4} - a {}^{3} - 2a {}^{2}$

7.

$( - x - 2)(2x {}^{3} - 3) = - x \times 2x { }^{3} - x \times ( - 3) - 2 \times 2x {}^{3} - 2 \times ( - 3) = - 2x {}^{4} + 3x - 4x {}^{3} + 6$

8.

$(3a {}^{2} - 5b)(5a {}^{2} + b) = 3a {}^{2} \times 5a {}^{2} + 3a {}^{2} b - 5b \times 5a {}^{2} - 5b \times b = 15a {}^{4} + 3a {}^{2} b - 25a {}^{2} b - 5b {}^{2} = 15a {}^{4} - 22a {}^{2} b - 5b {}^{2}$

9.

$(y + 3)(y {}^{2} - 2y + 5) = y \times (y {}^{2} - 2y + 5) + 3(y {}^{2} - 2y + 5) = y {}^{3} - 2y {}^{2} + 5y + 3y {}^{2} - 6y + 15 = y {}^{3} + y {}^{2} - y + 15$

10.

$(m + 3n)(m {}^{2} - 6mn - n {}^{2} ) = m \times (m {}^{2} - 6mn - n {}^{2} ) + 3n \times (m {}^{2} - 6mn - n {}^{2} ) = m {}^{3} - 6m {}^{2} n - mn {}^{2} + 3m {}^{2} n - 18mn {}^{2} - 3n {}^{3} = m {}^{3} - 3m {}^{2} n - 19mn {}^{2} - 3n {}^{3}$

11.

$2x \times (3x - 1)(2x + 5) = (6x {}^{2} - 2x)(2x + 5) = 12x {}^{3} + 30x {}^{2} - 4x {}^{2} - 10x = 12x {}^{3} + 26x {}^{2} - 10x$

12.

$- 3x {}^{2} \times (2 - 3x)(3x {}^{2} + 11x) = ( - 6x {}^{2} + 9x {}^{3} )(3x {}^{2} + 11x) = - 18x {}^{4} - 66x {}^{3} + 27x {}^{5} + 99x {}^{4} = 81x {}^{4} - 66x {}^{3} + 27x {}^{5} = 27x {}^{5} + 81x {}^{4} - 66x {}^{3}$