a,2x.(x3-3x2y+6xy3)
tính giá trị biểu thức C = x3 - 3x2y + y3 / 2x + y tại |x| = 1/2; |y| = 1
x3 + 8y3 - 3x2y - 6xy2
3x(4x2-1)=0
(x+5)2-(x+5)(x-2)=0
x3+7x2+6x=0
(x+1)2-(2x+3)2=0
a)
\(=\left(x+2y\right)\left(x^2-xy+y^2\right)-3xy\left(x+2y\right)\)
\(=\left(x+2y\right)\left(x^2-xy+y^2-3xy\right)\)
\(=\left(x+2y\right)\left(x^2-2xy+y^2\right)\)
\(=\left(x+2\right)\left(x-2\right)^2\)
b)
\(3x\left(2x-1\right)\left(2x+1\right)=0\)
3x=0 =>x=0
hoặc 2x-1=0 => 2x=1=>x=1/2
hoặc 2x+1=0=>2x=-1=>x=-1/2
Thực hiện phép tính:
a)(4x4y-7x2y+3y).(2y-3x2y)
b)(x2+3x-\(\dfrac{3}{2}\)x3):(2x)-\(\dfrac{x}{2}\).(1-\(\dfrac{3}{2}\)x)
c)(-2x3-x-3+5x2):(3-2x)
a: \(\dfrac{4x^4y-7x^2y+3y}{-3x^2+2y}\)
\(=\dfrac{4x^4y-4x^2y-3x^2y+3y}{-\left(3x^2-2y\right)}\)
\(=\dfrac{4x^2y\left(x^2-1\right)-3y\left(x^2-1\right)}{-\left(3x^2-2y\right)}\)
\(=\dfrac{y\left(x^2-1\right)\left(4x^2-3\right)}{-\left(3x^2-2y\right)}\)
a) `(4x^4y-7x^2y+3y).(2y-3x^2y)`
`=8x^4y^2-14x^2y^2+6y^2-12x^6y^2+21x^4y^2-9x^2y^2`
`=29x^4y^2-12x^6y^2-23x^2y^2+6y^2`
b) `(x^2+3x-3/2 x^3):2x - x/2 . (1-3/2 x)`
`=(x+3-3/2 x^2):2 - (x/2 - 3/4 x^2)`
`=x/2 + 3/2 - 3/4 x^2 -x/2 +3/4 x^2`
`=3/2`
c) `(-2x^3-x-3+5x^2):(3-2x)`
`=(3-2x)(x^2-x-1) : (3-2x)`
`=x^2-x-1`
Thương của phép chia (-12x4y + 4x3 – 8x2y2) : 4x2 là
A. -3x2y + x – 2y2 B. 3x4y + x3 – 2x2y2
C. 3x2y - x + 2y2 D. 3x2y – x + 2y2
Thực hiện phép tính:
a) - 10 y 3 x 2 : 3 x 2 y ; b) x 3 ( 2 y ) 4 z 2 : ( - 6 x 2 z 2 ) .
Phân tích đa thức thành nhân tử.
a) 5x - 10y
b) 3x2y - 6xy2
c) x(x - y) - 3(y - x)
d)2x(x - 1) + 4x2(1 - x)
e) x2- 4xy + 4y2
f) 9x2- 16y2
g) x3- 27.
\(a,=5\left(x-2y\right)\\ b,=3xy\left(x-2y\right)\\ c,=\left(x-y\right)\left(x+3\right)\\ d,=\left(x-1\right)\left(2x-4x^2\right)=2x\left(1-2x\right)\left(x-1\right)\\ e,=\left(x-2y\right)^2\\ f,=\left(3x-4y\right)\left(3x+4y\right)\\ g,=\left(x-3\right)\left(x^2+3x+9\right)\)
a. 5x - 10y
= 5(x - 2y)
b. 3x2y - 6xy2
= 3xy(x - 2y)
c. x(x - y) - 3(y - x)
= x(x - y) + 3(x - y)
= (x + 3)(x - y)
d. 2x(x - 1) + 4x2(1 - x)
= 2x(x - 1) - 4x2(x - 1)
= (2x - 4x2)(x - 1)
= 2x(1 - 2x)(x - 1)
e. x2 - 4xy + 4y2
= (x - 2y)2
f. 9x2 - 16y2
= (3x - 4y)(3x + 4y)
g. x3 - 27
= (x - 3)(x2 + 3x + 9)
Rút gọn phân thức: x 2 - y 2 y 3 - 3 x y 2 + 3 x 2 y - x 3 .
A. - x + y ( y - x ) 2
B. x + y ( y - x ) 2
C. - x - y ( y - x ) 2
D. - x + y ( y + x ) 2
Rút gọn phân thức sau: x 2 - y 2 y 3 - 3 x y 2 + 3 x 2 y - x 3 .
A. - x + y ( y - x ) 2
B. x + y ( y - x ) 2
C. - x - y ( y - x ) 2
D. - x + y ( y + x ) 2
Rút gọn phân thức sau: x 2 - y 2 y 3 - 3 x y 2 + 3 x 2 y - x 3 .
A. - x + y ( y - x ) 2
B. x + y ( y - x ) 2
C. - x - y ( y - x ) 2
D. - x + y ( y + x ) 2
Rút gọn phân thức sau: x 2 - y 2 y 3 - 3 x y 2 + 3 x 2 y - x 3 .
A. - x + y ( y - x ) 2
B. x + y ( y - x ) 2
C. - x - y ( y - x ) 2
D. - x + y ( y + x ) 2