rút gọn các bt sau:
(x-8)(x^2-2x+9)+(x+1)^3
(2x-1)^2-3(x-1)(x+2)-(x-3)^2
2(x+2)(x-2)+(x+3)(2x-1)
(x-2)(2x-1)-3(x+1)^2-4x(x+2)
x^2-2x+2/x^2-x+1=x^2/x^2+x+1=3/(x^4+x^2+1)x
\(\dfrac{x-x^2}{1-x^2}+\dfrac{1+x}{1+2x+x^2}+\dfrac{1-2x}{x-1}-\dfrac{x^3-1}{1-x^3}\) tại x=5
3x(x-5+1)=x(4+3x)
X(2x+1)-x(x-2)=4
2/x+1-2x+1/x^2-x+1=3/x^3+1
Bài 1 rút gọn
a) (x+3)(x-3)-(x-3)2
b) (2x+1)2+2(2x+1)(x-1)+(x-1)2
c) x(x-3)(x+3)-(x^2 +1)(x^2-1)
Bài 2 tìm x
a) (x+2)2-x^2-3x=21
b) x^2+x-12=0
c) x^3-3x^2+3x-126=0
d) x^3-5x^2+8x-4=0
e) 2x^3-x^2+3x+6=0
f) (x^2+x) (x^2+x+1)=6
Phân tích các đa thức sau thành nhân tử: A= ( x^2+x)^2 + 4x^2+ 4x -12 , B=(x^2+ x + 1) (x^2+x + 2) -12 , C=x(x+1)(x+2)(x+3) + 1. , D=(x-1)(x-3)(x-5)(x-7) - 20
1. x^2-y^2-2x+2y 2. x^3-x+3x^2y+3xy^2+y^3-y. 3. 4x^4y^4+1. 4. x^2-2x-4y^2-4y. 5.x^3-x^2-x+1. 6.x^2y-x^3-9y+9x. 7.x^3-2x^2+x-xy^2. 8.x^2-2x-4y^2-4y.
Rút gọn các biểu thức sau:
1)x(x-y)-(x+y)(x-y)
2)2a(a-1)-2(a+1)^2
3)(x+2)^2-(x-1)^2
4)x(x-3)^2-x(x+5)(x-2
tìm x
a)x^4-2x^3-25x^2+50x=0
b)x^2(x-1)-4x^2+8x-4=0
c)9x^2-4-2(3x-2)^2=0
d)9x^2+90x+225-(x-7)^2=0
e)x^3-8+(x-2)(x+1)=0
g)(x+1)(x+2)(x+3)(x+4)-24=0
giúp mk vs ah
bai 1; tim x
a) 5x(x -3)2 - 5(x - 1)3 + 15(x +2) (x-2)=5
b) (x+2) (3-4x) = x2 +4x-4
c) x2(x2 +1) - x2 -1=0
