\(d,\left(2x-1\right)^2=4x^2-4x+1\\ e,\left(x+6\right)^3=x^3+18x^2+108x+216\\ f,\left(x+3\right)\left(x^2-3x+9\right)-\left(54+x^3\right)=x^3+27-54-x^3=-27\)
Bài 1 Rút gọn biểu thức
a, [(3x - 2)(x + 1) - (2x + 5)(x2 - 1)] : (x + 1)
b, (2x + 1)2 - 2(2x + 1)(3 - x) + (3 - x)2
c, (x - 1)2 - (x + 1) (x2 - x + 1) - (3x + 1)(1 - 3x)
d, (x2 + 1)(x - 3) - (x - 3)(x2 + 3x + 9)
e, (3x +2)2 + (3x - 2)2 - 2(3x + 2)(3x - 2) + x
Bài 2 Phân tích các đa thức sau thành nhân tử
1, 3(x + 4) - x2 - 4x
2, x2 - xy + x - y
3, 4x2 -25 + (2x + 7)(5 - 2x)
4, x2 + 4x - y2 + 4
5, x3 - x2 - x + 1
6, x3 + x2y - 4x - 4y
7, x3 - 3x2 + 1 - 3x
8, 2x2 + 3x - 5
9, x2 - 7xy + 10y2
10, x3 - 2x2 + x - xy2
Phân tích đa thức thành nhân tử:
c) 16-x2+2xy-y2
d) (x-1)2-4(2x-3)2
e) x3-3x2+3x-1
f) x2-7
Tìm x biết:
a/ x2 - 6x = 0 b/ ( 3x – 1)2 – ( x + 5)2 = 0
c/ 9x2 ( x- 1) = x – 1 d/ x2 – 4 = ( x – 2)2
e/ x + 3 – ( x + 3)2 =0 f/ x3 – 0,36x = 0
g/ 5x( x- 2018) – x + 2018 = 0 h/ x( x- 5) – 4x + 20 = 0
Bài 2: Phân tích đa thức sau thành nhân tử:
a) x4 - y4
b) x2 - 3y2
c) (3x - 2y)2 - (2x - 3y)2
d) 9(x - y)2 - 4(x + y)2
e) (4x2 - 4x + 1) - (x + 1)2
f) x3 + 27
g) 27x3 - 0,001
h) 125x3 - 1
(x-3)(x2+3x+9)-(54+x3)
Rút gọn:
a) x3+12x2+48x+64
b)x3-6x2+12x-8
c)(x+2) (x2-2x+4)
d) (x-3) (x2+3x+9)
a)A=3x(2/3x2-3x4)+(3x2)(x3-1)+(-2+9).x2-12
b)B=x(2x3+x+2)-2x2(x2+1)+x2-2x+1
c)C=x.(2x+1)-x2(x+2)+x3-x+3
Rút gọn : ( x+3).(x2-3x+9)-( 54+x3)
a) 3x(x+1)-x(3x+2)
b) 2x(x2-5x+6)+(x-1)(x+3)
c) (x2-xy+y2)-(x2+2xy+y2)
d) (2/5xy+x-y)-(3x+4y)-2/5xy
e) 2xy(x2-4xy+4y2)
f) (x+y)(xy+5)
g) (x3-2x2-x+2):(x-1)
h) (2x2+3x-2):(2x-1)
