Phân tích các đa thức sau thành nhân tử
a) \(8a^2xy-18b^2xy\)
b) \(32a^2b^2-4\)
c) \(x^2-49z^2-4xy+4y^2\)
d) \(3x^2+6x+3-3y^2\)
e) \(12x^2y-12y^3+36xy+27y\)
phân tích đa thức sau thành nhân tử
a\(12x^3y-24x^2y^2+12xy^3\)
b\(x^2-6x+xy-6y\)
c\(2x^2+2xy-x-y\)
d\(ax-2x-a^2+2a\)
e\(x^3-3x^2+3x-1\)
f\(3x^2-3y^2-12x-12y\)
b: \(x^2-6x+xy-6y\)
\(=x\left(x-6\right)+y\left(x-6\right)\)
\(=\left(x-6\right)\left(x+y\right)\)
c: \(2x^2+2xy-x-y\)
\(=2x\left(x+y\right)-\left(x+y\right)\)
\(=\left(x+y\right)\left(2x-1\right)\)
e: \(x^3-3x^2+3x-1=\left(x-1\right)^3\)
Phân tích các đa thức sau thành nhân tử:
a,x^2-4xy+4y^2
b,4x^4+9y^2-12x^2y
c,x^2-3xy+x-3y
d,x^3-x^2-5x+125
e,x^2-y^2+6x+9
f,x^3+3x^2-9x-27
g,x^2-4y^2+4y-1
h,x^4+3x^3-9x-9
i,8x^3-36x^2y+54xy^2-27y^3
Phân tích các đa thức sau thành nhân tử:
a,x^2-4xy+4y^2
b,4x^4+9y^2-12x^2y
c,x^2-3xy+x-3y
d,x^3-x^2-5x+125
e,x^2-y^2+6x+9
f,x^3+3x^2-9x-27
g,x^2-4y^2+4y-1
h,x^4+3x^3-9x-9
i,8x^3-36x^2y+54xy^2-27y^3
Phân tích các đa thức sau thành nhân tử :
a, A= \(x^3+3x^2y-4xy^2-12y^3\)
b, B= \(x^2+4y^2-2xy+x^2+8y^3\)
A= \(^{x^3+3x^2y-4xy^2-12y^3=x^2\left(x+3y\right)-4y^2\left(x+3y\right)=\left(x+3y\right)\left(x^2-4y^2\right)}\)
Phân tích đa thức sau thành nhân tử
a) (a^2+b^2)^2-4a^2b^2
b) 3x^2-3xy-5x+5y
c) -x^3+3x^2 -3x+1
d) 2x^2+4xy+2y^2- 8z^2
e) a^3-a^2-a+1
f) x^3-2xy-x^2y+2y^2
e) Ta có: \(a^3-a^2-a+1\)
\(=a^2\left(a-1\right)-\left(a-1\right)\)
\(=\left(a-1\right)\left(a^2-1\right)\)
\(=\left(a-1\right)^2\cdot\left(a+1\right)\)
f) Ta có: \(x^3-2xy-x^2y+2y^2\)
\(=x^2\left(x-y\right)-2y\left(x-y\right)\)
\(=\left(x-y\right)\left(x^2-2y\right)\)
a) \(\left(a^2+b^2\right)^2-4a^2b^2=\left(a^2+b^2+2ab\right)\left(a^2+b^2-2ab\right)=\left(a+b\right)^2.\left(a-b\right)^2\)
b) \(3x^2-3xy-5x+5y=3x\left(x-y\right)-5\left(x-y\right)=\left(x-y\right)\left(3x-5\right)\)
c) \(-x^3+3x^2-3x+1=\left(1-x\right)^3\)
d) Đề sai ko ???
e) \(a^3-a^2-a+1=a^2\left(a-1\right)-\left(a-1\right)=\left(a-1\right)\left(a^2-1\right)=\left(a-1\right)^2\left(a+1\right)\)
f) \(x^3-2xy-x^2y+2y^2=x^2\left(x-y\right)-2y\left(x-y\right)=\left(x-y\right)\left(x^2-2y\right)\)
a, \(=\left(a^2+b^2-2ab\right)\left(a^2+b^2+2ab\right)=\left(\left(a-b\right)\left(a+b\right)\right)^2=\left(a^2-b^2\right)^2\)
\(b,=3x\left(x-y\right)-5\left(x-y\right)=\left(x-y\right)\left(3x-5\right)\)
\(c,=-\left(x^2-3x^2+3x-1\right)=-\left(x-1\right)^3\)
\(d,=2\left(x^2+2xy+y^2-4z^2\right)=2\left(\left(x+y\right)^2-4z^2\right)=2\left(x+y-2z\right)\left(x+y+2z\right)\)
\(e,=a^2\left(a-1\right)-\left(a-1\right)=\left(a-1\right)\left(a^2-1\right)\)
\(f,=x^2\left(x-y\right)-2y\left(x-y\right)=\left(x^2-2y\right)\left(x-y\right)\)
bài 1 phân tích đa thức thành nhân tử
a)3x(x-7)+2xy-14y
b)9(2x-5)^2+15x-6x^2
c)6x^2 -12x+6
d)-20x^2+60xy-45y^2
e)2xy^3-16x^4
f)3x^4-48
g)x^2-z^2+4xy+4y^2
h)x^2-z^2+2xy-6zt+y^2-9t^2
baif2 pt đa thức thanhhf nhân tử
a)x^2-12x+20
b)2x^2-x-15
c)x^3-x^2+x-1
d)2x^3-5x-6
e)4y^4+1
f)x^7+x^5+x^3
g)(x^2+x)^2-5(x^2+x)+6
h)(x^2+2x)^2-2(x+1)^2-1
i)x^2+4xy+4y^2-4(x+2y)+3
j)x(x+1)(x+2)(x+3)-3
2:
a: \(x^2-12x+20\)
\(=x^2-2x-10x+20\)
=x(x-2)-10(x-2)
=(x-2)(x-10)
b: \(2x^2-x-15\)
=2x^2-6x+5x-15
=2x(x-3)+5(x-3)
=(x-3)(2x+5)
c: \(x^3-x^2+x-1\)
=x^2(x-1)+(x-1)
=(x-1)(x^2+1)
d: \(2x^3-5x-6\)
\(=2x^3-4x^2+4x^2-8x+3x-6\)
\(=2x^2\left(x-2\right)+4x\left(x-2\right)+3\left(x-2\right)\)
\(=\left(x-2\right)\left(2x^2+4x+3\right)\)
e: \(4y^4+1\)
\(=4y^4+4y^2+1-4y^2\)
\(=\left(2y^2+1\right)^2-\left(2y\right)^2\)
\(=\left(2y^2+1-2y\right)\left(2y^2+1+2y\right)\)
f; \(x^7+x^5+x^3\)
\(=x^3\left(x^4+x^2+1\right)\)
\(=x^3\left(x^4+2x^2+1-x^2\right)\)
\(=x^3\left[\left(x^2+1\right)^2-x^2\right]\)
\(=x^3\left(x^2-x+1\right)\left(x^2+x+1\right)\)
g: \(\left(x^2+x\right)^2-5\left(x^2+x\right)+6\)
\(=\left(x^2+x\right)^2-2\left(x^2+x\right)-3\left(x^2+x\right)+6\)
\(=\left(x^2+x\right)\left(x^2+x-2\right)-3\left(x^2+x-2\right)\)
\(=\left(x^2+x-2\right)\left(x^2+x-3\right)\)
\(=\left(x^2+x-3\right)\left(x+2\right)\left(x-1\right)\)
h: \(\left(x^2+2x\right)^2-2\left(x+1\right)^2-1\)
\(=\left(x^2+2x+1-1\right)^2-2\left(x+1\right)^2-1\)
\(=\left[\left(x+1\right)^2-1\right]^2-2\left(x+1\right)^2-1\)
\(=\left(x+1\right)^4-2\left(x+1\right)^2+1-2\left(x+1\right)^2-1\)
\(=\left(x+1\right)^4-4\left(x+1\right)^2\)
\(=\left(x+1\right)^2\left[\left(x+1\right)^2-4\right]\)
\(=\left(x+1\right)^2\left(x+1+2\right)\left(x+1-2\right)\)
\(=\left(x+1\right)^2\cdot\left(x+3\right)\left(x-1\right)\)
i: \(x^2+4xy+4y^2-4\left(x+2y\right)+3\)
\(=\left(x+2y\right)^2-4\left(x+2y\right)+3\)
\(=\left(x+2y\right)^2-\left(x+2y\right)-3\left(x+2y\right)+3\)
\(=\left(x+2y\right)\left(x+2y-1\right)-3\left(x+2y-1\right)\)
\(=\left(x+2y-1\right)\left(x+2y-3\right)\)
j: \(x\cdot\left(x+1\right)\left(x+2\right)\left(x+3\right)-3\)
\(=\left(x^2-3x\right)\left(x^2-3x+2\right)-3\)
\(=\left(x^2-3x\right)^2+2\left(x^2-3x\right)-3\)
\(=\left(x^2-3x+3\right)\left(x^2-3x-1\right)\)
Bài 1: Phân tích đa thức sau :
a)2x(xy+y^2-3)
b)(x-y)(2x+y)
c)(x-2y)^2
d)(2x-y)(y+2x)
bài 2: Phân tích các đơn thức thành nhân tử
a)3x^2-3xy
b)x^2-4y^2
c)3x-3y+xy-y^2
d)x^2-1+2y-y^2
Bài 3: Tìm x biết:
a)3x^2-6x=0
b)Tìm x,y thuộc z biết: x^2+4y^2-2xy=4
Bài 2:
a: \(3x^2-3xy=3x\left(x-y\right)\)
b: \(x^2-4y^2=\left(x-2y\right)\left(x+2y\right)\)
c: \(3x-3y+xy-y^2=\left(x-y\right)\left(3+y\right)\)
d: \(x^2-y^2+2y-1=\left(x-y+1\right)\left(x+y-1\right)\)
Tìm bậc của các đa thức sau:
a) \(x^3y^3+6x^2y^2+12xy-8
\)
b) \(x^2y+2xy^2-3x^3y+4xy^5\)
c) \(x^6y^2+3x^6y^3-7x^5y^7+5x^4y\)
d) \(2x^3+x^4y^5+3xy^7-x^4y^5+10-xy^7\)
e) \(0,5x^2y^3+3x^2y^3z^3-a.x^2y^3-x^4-x^2y^3\) với a là hằng số
a, bậc 6
b, bậc 6
c, bậc 12
d, bậc 9
e, bậc 8