Lep で Контрольная работа Формула сокращенного - умножения ла الد Вариант a) (x+4)=x²+24+4² = x²+8x+16 2 d) (a-2b)²= a²-2-2.26 +2b²= a²-4ab - 46 32 2 b) (3+5) (dy-5) = 3y² - 5²= gy² - 26 N2 a) a²-6422-8²= (a-8) (ats) 2 )48x²-164² = 7x² - 4y = (7x-4y) (2x +44) 2 b) 25x²- 10x y+y² = (2x-3) N3 d) (3+4x)²-2x = 3+ 2.3.4x+4x²-24メン 9+2+x+16x=24x = 8+16x² 2 2 8) 3(are)²-6ac=種間 = a²-630-6ac= =30+30-6ac 9- b) (c-2) (C+3)-(c-1)² = c²+SC-2C-6-(C-1)²= +30-20-6-9-12-0-7 مالد б) 16-810-42-80² = (4-ga) (4+98) b) 2x + x + 2y = 2y = x xy² (2723) 4) (12) - 44 = (942) - (29) = (g02-24) (482-23) 2 2 4 قابر 5 2 = 6x-2.6X (x²)² = 36x²-12x²+x-x² (x-1)(x+1) 66x (3+2x) = 2 4 94 36×ー+メーカーズートx18x+hx = =36X- S 36x-1+18x=36x²-1+18x 18X+12 livala

№1

• а) \[(x+4)^2 = x^2 + 2 \cdot x \cdot 4 + 4^2 = x^2 + 8x + 16\]
• б) \[(a-2b)^2 = a^2 - 2 \cdot a \cdot 2b + (2b)^2 = a^2 - 4ab + 4b^2\]
• в) \[(3y+5)(3y-5) = (3y)^2 - 5^2 = 9y^2 - 25\]

№2

• а) \[a^2 - 64 = a^2 - 8^2 = (a-8)(a+8)\]
• б) \[49x^2 - 16y^2 = (7x)^2 - (4y)^2 = (7x-4y)(7x+4y)\]
• в) \[25x^2 - 10xy + y^2 = (5x-y)^2\]

№3

• а) \[(3+4x)^2 - 24x = 9 + 2 \cdot 3 \cdot 4x + (4x)^2 - 24x = 9 + 24x + 16x^2 - 24x = 9 + 16x^2\]
• б) \[3(a+c)^2 - 6ac = 3(a^2 + 2ac + c^2) - 6ac = 3a^2 + 6ac + 3c^2 - 6ac = 3a^2 + 3c^2\]

№4

• б) \[16 - 81a^2 = 4^2 - (9a)^2 = (4 - 9a)(4 + 9a)\]
• в) \[2x^2 + 4xy + 2y^2 = 2(x^2 + 2xy + y^2) = 2(x+y)^2\]
• а) \[(x+2)^2 - 4y^2 = (x+2)^2 - (2y)^2 = (x+2-2y)(x+2+2y)\]

№5

• \[(6x-x^2)^2 - (x-1)(x+1) + 6x(3+2x) = (6x-x^2)^2 - (x^2 - 1) + 18x + 12x^2 = \]
• \[= 36x^2 - 12x^3 + x^4 - x^2 + 1 + 18x + 12x^2 = x^4 - 12x^3 + 47x^2 + 18x + 1\]
• \[(c-2)(c+3) - (c-1)^2 = c^2 + 3c - 2c - 6 - (c^2 - 2c + 1) = c^2 + c - 6 - c^2 + 2c - 1 = 3c - 7\]

Ответ: См. решение выше