\(\left(x^3+2x^2-x-2\right):\left(x+2\right)\\ =\left[\left(x^3+2x^2\right)-\left(x+2\right):\left(x+2\right)\right]\\ =\left[x^2\left(x+2\right)-\left(x+2\right):\left(x+2\right)\right]\\ =\left(x^2-1\right)\left(x+2\right):\left(x+2\right)\\ =x^2-1\)
Tìm x, biết:
a) 2(5x-8)-3(4x-5) = 4(3x-4) + 11;
b) 2 x ( 6 x - 2 x 2 ) + 3 x 2 ( x - 4 ) = 8;
c) 2 ( x 3 - 1 ) - 2 x 2 ( x + 2 x 4 ) + ( 4 x 5 + 4 ) x = 6;
d)(2x)2(4x-2)-(x3 -8x2) = 15.
x3-2x2-x-2=0 (tìm x)
Thực hiện phép chia:
a) ( x 3 - 2 x 2 - 15x + 36) : (x + 4);
b) ( 2 x 4 + 2 x 3 + 3 x 2 - 5x - 20) : ( x 2 + x + 4);
c) (2 x 3 + 11 x 2 + 18x-3) : (2x + 3);
d) (2x3 + 9x2 +5x + 41) : (2x2 - x + 9).
x3-2x2+x+2>0
x3 – 2x2 + x – 2 =0
Trong các khai triển dưới đây, khai triển nào là đúng?
A. (x-2)3 = x3 - 6x2 +12x-8
B. (x-2)3 = x3 - 2x2 + 4x -8
C. (x-2)3 = 3x3 - 6x2 + 12x -24
D. (x-2)3 = x3 - 6x2 + 12x + 8
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
11,18y2 - 12xy + 2x2
12,(x2+x)2 + 3(x2+x) + 2
13,5x2 - 10xy + 5y2 - 20z2
14,x3 - 9x + 2x2 - 18
15,x2 - 2x - 4y2 - 4y
16,a2 + 2ab + b2 - 2a - 2b + 1
17,x3 - x + 3x2 y + 3xy2 + y3 - y
18,x3 + y3 + z3 - 3xyz
19,x2 + 4x - 5
20,2x2 - 6x - 8
21,x2 - 10xy + 9y2
22,5xz - 5xy - x2 + 2xy - y2
23,(x2 + x + 1) ( x2 + x + 2) - 12
24,(x+1) (x+2) (x+3) (x+4) - 24
25,x3 + 2x2 - 2x - 12
Bài 3: Phân tích đa thức sau thành nhân tử.
a) x4 + 2x2 + 1
b) 4x2 - 12xy + 9y2
c) -x2 - 2xy - y2
d) (x + y)2 - 2(x + y) + 1
e) x3 - 3x2 + 3x - 1
g) x3 + 6x2 + 12x + 8
h) x3 + 1 - x2 - x
k) (x + y)3 - x3 - y3
