4/ 2x2 (x+1)+4(x+1)
5/ -3x-6xy+9xz
6/ 2x2y -4xy2+ 6xy
Giải giùm mình với nhé!!!
phân tích thành nhân tử
1) 2x2(x+1) + 4(x+1)
2) -3x - 6xy - 9xz
3) 2x2y - 4xy2 + 6xy
4) 4x3y2 - 8x3y2 + 2x4y
\(2x^2\left(x+1\right)+4\left(x+1\right)=2\left(x+1\right)\left(x^2+2\right)\)
\(-3x-6xy-9xz=-3x\left(1+2y+3z\right)\)
\(2x^2y-4xy^2+6xy=2xy\left(x-2y+3\right)\)
\(4x^3y^2-8x^3y^2+2x^4y=-4x^3y^2+2x^4y=2x^3y\left(x-2y\right)\)
1) \(2x^2\left(x+1\right)+4\left(x+1\right)=2\left(x+1\right)\left(x^2+2\right)\)
2) \(-3x-6xy-9xz=-3x\left(1+2y+3z\right)\)
3) \(2x^2y-4xy^2+6xy=2xy\left(x-2y+3\right)\)
4) \(4x^3y^2-8x^3y^2+2x^4y=-4x^3y^2+2x^4y=-2x^3y\left(2y-x\right)\)
a/ 2x3 (2xy + 6x5y) b/ 3 1 x 5y 3 ( 4xy2 + 3x + 1) c/ 4 1 x 3yz (-2x2y 4 – 5xy) d/ (2x3 + 5y2 )(4xy3 + 1) e/ (5x – 2y)(x2 – xy + 1) f/ (x – 1)(x + 1)(x + 2)
BÀI TẬP PHÂN TÍCH ĐA THỨC THÀNH NHÂN TỬ BẰNG PHƯƠNG PHÁP ĐẶT NHÂN TỬ CHUNG
1) xy3 – x3y
2) 15xy + 20x2 – 30x
3)6x – 3xy
4)x3 + 2x2 + x
5)4x3 – 12x2 + 9x
6)2x2y + 4xy2 – 10 x3y2
7)x4 + 2x3 + x2
11)x(x – 1) – y(1 – x)
1, \(xy^3-x^3y=xy\left(y^2-x^2\right)=xy\left(y-x\right)\left(x+y\right)\)
2, \(5x\left(3y+4x-6\right)\)
3, \(3x\left(2-y\right)\)
4, \(x\left(x^2+2x+1\right)=x\left(x+1\right)^2\)
5, \(x\left(4x^2-12x+9\right)=x\left(2x-3\right)^2\)
6, \(2xy\left(x+2y-5x^2y\right)\)
7, \(x^2\left(x^2+2x+1\right)=x^2\left(x+1\right)^2\)
11, \(\left(x+y\right)\left(x-1\right)\)
\(1,xy^3-x^3y=xy\left(y^2-x^2\right)=xy\left(y-x\right)\left(y+x\right)\\ 2,15xy+20x^2-30x=5x\left(3y+4x-6\right)\\ 3,6x-3xy=3x\left(2-y\right)\\ 4,x^3+2x^2+x=x\left(x^2+2x+1\right)=x\left(x+1\right)^2\\ 5,4x^3-12x^2+9x=x\left(4x^2-12x+9\right)=x\left(2x-3\right)^2\\ 6,2x^2y+4xy^2-10x^3y^2=2xy\left(x+2y-5x^2y\right)\\ 11,x\left(x-1\right)-y\left(1-x\right)=x\left(x-1\right)+y\left(x-1\right)=\left(x-1\right)\left(x+y\right)\)
Bài1:Làm tính nhân:
a) 2x. (x2– 7x -3) b) ( -2x3+ y2-7xy). 4xy2 c)(-5x3).(2x2+3x-5)
d)(x2-2x+3). (x-4) e) ( 2x3-3x -1). (5x+2) g) 3(2x-1)-5(x-3)
\(a,=2x^3-14x^2-6x\\ b,=-8x^4y^2+4xy^4-28x^2y^3\\ c,=-10x^5-15x^4+25x^3\\ d,=x^3-4x^2-2x^2+8x+3x-12=x^3-6x^2+11x-12\\ e,=10x^4+4x^3-15x^2-6x-5x-2=10x^4+4x^3-15x^2-11x-2\\ g,=6x-3-5x+15=x+12\)
a) 2x. (x2 – 7x -3)
b) ( -2x3 + y2 -7xy). 4xy2
c)(-5x3). (2x2+3x-5)
d) (2x2 - xy+ y2).(-3x3)
e)(x2 -2x+3). (x-4)
f) ( 2x3 -3x -1). (5x+2)
mk cần gấp lắm nhanh hộ mk nhé!
a) \(2x\left(x^2-7x-3\right)=2x^3-14x^2-6x\)
b) \(\left(-2x^3+y^2-7xy\right)\cdot4xy^2=-8x^4y^2+4xy^4-28x^2y^3\)
c) \(\left(-5x^3\right)\left(2x^2+3x-5\right)=-10x^5-15x^4+25x^3\)
d) \(\left(2x^2-xy+y^2\right)\left(-3x^3\right)=-6x^5+3x^4y-3x^3y^2\)
e) \(\left(x^2-2x+3\right)\left(x-4\right)=x^3-4x^2-2x^2+8x+3x-12=x^3-6x^2+11x-12\)
f) \(\left(2x^3-3x-1\right)\cdot\left(5x+2\right)=5x\left(2x^3-3x-1\right)+2\left(2x^3-3x-1\right)=10x^4-15x^2-5x+4x^3-6x-2=10x^4+4x^3-15x^2-11x-2\)
Bài 1: Thực hiện phép tính
a/ 5x2y (x2y– 4xy2 + 7xy)
b/ 3xy2 (x2y3 + x 2y – xy2 )
c/ 3x(12x2 + 4x – 5) + 2x(9x2 – 6x + 7)
d/ 5x(2x2 – 9x – 5) – 9x (x2 - 7x – 4)
a/ 5x2y (x2y– 4xy2 + 7xy)
`=5x^4y^2-20x^3y^3+35x^3y^2`
b/ 3xy2 (x2y3 + x 2y – xy2 )
`=3x^3y^5+3x^3y^3-3x^2y^4`
c/ 3x(12x2 + 4x – 5) + 2x(9x2 – 6x + 7)
`=36x^3+12x^2-15x+18x^3-18x^2+14x`
`=54x^3-6x^2-x`
d/ 5x(2x2 – 9x – 5) – 9x (x2 - 7x – 4)
`=10x^3-45x^2-25x-9x^3+63x^2+36x`
`=x^3+18x^2+11x`
Cho 2 các đa thức
A= 3x2y+5xy2-2xy+1
B= 2x2y-7xy2+6xy-8
C=-5x2y+4xy2-4xy+12
Tìm x biết A+B+C=0 và y=-2
Ta có: \(A+B+C=0\)
\(\Leftrightarrow3x^2y+5xy^2-2xy+1+2x^2y-7xy^2+6xy-8-5x^2y+4xy^2-4xy+12=0\)
\(\Leftrightarrow2xy^2+5=0\)
\(\Leftrightarrow2x\cdot\left(-2\right)^2+5=0\)
\(\Leftrightarrow8x+5=0\)
\(\Leftrightarrow8x=-5\)
hay \(x=-\dfrac{5}{8}\)
Vậy: \(x=-\dfrac{5}{8}\)
Cho các biểu thức đại số:
4xy2; 3 – 2y; - 3 5 x2 y3x; 10x + y;
5(x + y); 2x2 - 1 2 y3x; 2x2y; -2y.
Hãy sắp xếp chúng thành hai nhóm:
Nhóm 1: Những biểu thức có chứa phép cộng, phép trừ.
Nhóm 2: Các biểu thức còn lại.
Ta sắp xếp như sau:
Nhóm 1: 3 – 2y; 10x + y; 5(x+y)
Nhóm 2: 4xy2; x2 y3x; 2x2 y3x; 2x2y; -2y
Bài 1: Làm tính nhân:
a) 2x. (x2 – 7x -3) b) ( -2x3 + y2 -7xy). 4xy2
c)(-5x3). (2x2+3x-5) d) (2x2 - xy+ y2).(-3x3)
e)(x2 -2x+3). (x-4) f) ( 2x3 -3x -1). (5x+2)
g) ( 25x2 + 10xy + 4y2). ( ( 5x – 2y) h) ( 5x3 – x2 + 2x – 3). ( 4x2 – x + 2)
a) \(2x\left(x^2-7x-3\right)=2x.x^2-2x.7x-2x.3=2x^3-14x^2-6x\)
b) \(\left(-2x^3+y^2-7xy\right)4xy^2=\left(-2x^3\right)4xy^2+y^24xy^2-7xy.4xy^2=-8x^4y^2+4xy^4-28x^2y^3\)
c) \(\left(-5x^3\right)\left(2x^2+3x-5\right)=-5x^32x^2-5x^33x-5x^3.-5=-10x^5-15x^4+25x^3\)
d) \(\left(2x^2-xy+y^2\right)\left(-3x^3\right)=-3x^32x^2-3x^3.-xy-3x^3y^2=-6x^5+3x^4y-3x^3y^2\)
e) \(\left(x^2-2x+3\right)\left(x-4\right)=x\left(x^2-2x+3\right)-4\left(x^2-2x+3\right)=x^3-2x^2+3x-4x^2+8x-12=x^3-6x^2+11x-12\)
f) \(\left(2x^3-3x-1\right)\left(5x+2\right)=5x\left(2x^3-3x-1\right)+2\left(2x^3-3x-1\right)=10x^4-15x^2-5x+4x^3-6x-2=10x^4+4x^3-15x^2-11x-2\)
g)
\(\left(25x^2+10xy+4y^2\right).\left((5x-2y\right)\)
\(=125x^3-50x^2y+20x^2y-20xy^2+20xy^2-8y^3\)
\(=125x^3-30x^2y+8y^3\)
h)
\(\left(5x^3-x^2+2x-3\right)\left(4x^2-x+2\right)\)
\(=20x^5-5x^4+10x^3-4x^4+x^3-2x^2+8x^3-2x^2+4x-12x^2+3x-6\)
\(=20x^5-9x^4+19x^3-16x^2+7x-6\)