Question

РЕШИТЕ ПОЖАЛУЙСТА!!! 1) (a-4)(b+7) 2) (a-8)(-b+3) 3) (x-5)(x+7) 4) (a+3)(a^2-a-2) 5) -8(y+1)(y-5) 6) (3a+5)(3a-6)+33 7) 7x-(3x+1)(5x+1) 8) (y+3)(y+4)-y(y-1)

Answer 1

Ответ:

1)=ab+7a-4b-4×7=ab+7a-4b-28

2)=(-ab)+3a-8×(-b)-8×3=(-ab)+3a+8b-24

3)=x×x+7x-5x-5×7=x²+7x-5x-35=x²+2x-35

4)=a×(a²-a-2)+3(a²-a-2)=a³-a²-2a+3a²-3a-6=a³+2a²-5a-6

5)=(-8y-8)×(y-5)=(-8y²)-40y-8y+40=(-8y²)+32y+40

6)=9a²-18a+15a-30+33=9a²-3a+3

7)=7x-(15x²+3x+5x+1)=7x-(15x²+8x+1)=7x-15x²-8x-1=-x-15x²-1

8)=y²+4y+3y+12-y²+y=4y+3y+12+y=8y+12

Объяснение:

Answer 2

Давайте разберем каждое уравнение по порядку:

1. $(a-4)(b+7)$:

a \cdot b + a \cdot 7 - 4 \cdot b - 4 \cdot 7 = ab + 7a - 4b - 28\] 2) \((a-8)(-b+3)\): \[ a \cdot (-b) + a \cdot 3 - 8 \cdot (-b) - 8 \cdot 3 = -ab + 3a + 8b - 24\] 3) \((x-5)(x+7)\): \[ x \cdot x + x \cdot 7 - 5 \cdot x - 5 \cdot 7 = x^2 + 2x - 35\] 4) \((a+3)(a^2-a-2)\): \[ a^3 - a^2 - 2a + 3a^2 - 3a - 6 = a^3 - a^2 - 5a - 6\] 5) \(-8(y+1)(y-5)\): \[ -8 \cdot y \cdot y - 8 \cdot y \cdot (-5) - 8 \cdot 1 \cdot y - 8 \cdot 1 \cdot (-5) = -8y^2 + 48y + 40\] 6) \((3a+5)(3a-6)+33\): \[ 9a^2 - 18a + 15a - 30 + 33 = 9a^2 - 3a + 3\] 7) \(7x-(3x+1)(5x+1)\): \[ 7x - (15x^2 + 8x + 1) = -15x^2 - x - 1\] 8) \((y+3)(y+4)-y(y-1)\): \[ y^2 + 4y + 3y + 12 - y^2 + y = 7y + 12\]