Bài 1: Phân tích đa thức thành nhân tử
a) x3-2x2-5x+6
b) x4+5x2+6
c) x3+4x2+5x+2
d) x4+324
Bài 1:phân tích đa thức thành nhân tử
a)x2-2x-4y2-4y e)x4+2x3+2x2+2x+1
b)x3+2x2+2x+1 f)x5+x4+x3+x2+x+1
c)x3-4x2+12x-27
d)a6-a4+2a3+2a2
Làm chi tiết giúp mình với ạ, cảm ơn
a) \(x^2-2x-4y^2-4y=\left(x^2-4y^2\right)-\left(2x+4y\right)=\left(x-2y\right)\left(x+2y\right)-2\left(x+2y\right)=\left(x+2y\right)\left(x-2y-2\right)\)
b) \(x^3+2x^2+2x+1=\left(x+1\right)\left(x^2-x+1\right)+2x\left(x+1\right)=\left(x+1\right)\left(x^2-x+1+2x\right)=\left(x+1\right)\left(x^2+x+1\right)\)
c) \(x^3-4x^2+12x-27=x^3-3x^2-x^2+3x+9x-27=x^2\left(x-3\right)-x\left(x-3\right)+9\left(x-3\right)=\left(x-3\right)\left(x^2-x+9\right)\)
d) \(a^6-a^4+2a^3+2a^2=a^2\left(a^4-a^2+2a+2\right)=a^2\left[a^2\left(a-1\right)\left(a+1\right)+2\left(a+1\right)\right]=a^2\left(a+1\right)\left(a^3-a^2+2\right)=a^2\left(a+1\right)\left[a^3+a^2-2a^2+2\right]=a^2\left(a+1\right)\left[a^2\left(a+1\right)-2\left(a-1\right)\left(a+1\right)\right]=a^2\left(a+1\right)^2\left(a^2-2a+2\right)\)
a) Ta có: \(x^2-2x-4y^2-4y\)
\(=\left(x^2-4y^2\right)-\left(2x+4y\right)\)
\(=\left(x-2y\right)\left(x+2y\right)-2\left(x+2y\right)\)
\(=\left(x+2y\right)\left(x-2y-2\right)\)
b) Ta có: \(x^3+2x^2+2x+1\)
\(=\left(x^3+1\right)+2x\left(x+1\right)\)
\(=\left(x+1\right)\left(x^2-x+1\right)+2x\left(x+1\right)\)
\(=\left(x+1\right)\left(x^2+x+1\right)\)
d) Ta có: \(a^6-a^4+2a^3+2a^2\)
\(=a^2\left(a^4-a^2+2a+2\right)\)
\(=a^2\left[a^2\left(a^2-1\right)+\left(2a+2\right)\right]\)
\(=a^2\left[a^2\left(a-1\right)\left(a+1\right)+2\left(a+1\right)\right]\)
\(=a^2\cdot\left(a+1\right)\left(a^3-a+2\right)\)
c) Ta có: \(x^3-4x^2+12x-27\)
\(=\left(x^3-27\right)-\left(4x^2-12x\right)\)
\(=\left(x-3\right)\left(x^2+3x+9\right)-4x\left(x-3\right)\)
\(=\left(x-3\right)\left(x^2-x+9\right)\)
Bài 1: phân tích đa thức thành nhân tử
a)x2-y2-2x-2y e)x4-2x3+2x-1
b)x2(x+2y)-x-2y f)x4+x3+2x2+x+1
c)x3-4x2-9x+36 g)x2y+xy2+x2z+y2z+2xyz
d)x4+2x3+2x-1 h)3x3-3y2-2(x-y)2
Làm chi tiết giúp mình với ạ , cảm ơn
e) Ta có: \(x^4-2x^3+2x-1\)
\(=\left(x^4-1\right)-2x\left(x^2-1\right)\)
\(=\left(x^2+1\right)\left(x-1\right)\left(x+1\right)-2x\left(x-1\right)\left(x+1\right)\)
\(=\left(x-1\right)\left(x+1\right)\cdot\left(x^2-2x+1\right)\)
\(=\left(x+1\right)\cdot\left(x-1\right)^3\)
h) Ta có: \(3x^2-3y^2-2\left(x-y\right)^2\)
\(=3\left(x^2-y^2\right)-2\left(x-y\right)^2\)
\(=3\left(x-y\right)\left(x+y\right)-2\left(x-y\right)^2\)
\(=\left(x-y\right)\left(3x+3y-2x+2y\right)\)
\(=\left(x-y\right)\left(x+5y\right)\)
a) Ta có: \(x^2-y^2-2x-2y\)
\(=\left(x-y\right)\left(x+y\right)-2\left(x+y\right)\)
\(=\left(x+y\right)\left(x-y-2\right)\)
b) Ta có: \(x^2\left(x+2y\right)-x-2y\)
\(=\left(x+2y\right)\left(x^2-1\right)\)
\(=\left(x+2y\right)\left(x-1\right)\left(x+1\right)\)
c) Ta có: \(x^3-4x^2-9x+36\)
\(=x^2\left(x-4\right)-9\left(x-4\right)\)
\(=\left(x-4\right)\left(x^2-9\right)\)
\(=\left(x-4\right)\left(x-3\right)\left(x+3\right)\)
d) Ta có: \(x^4+2x^3+2x-1\)
\(=\left(x^2-1\right)\left(x^2+1\right)+2x\left(x^2+1\right)\)
\(=\left(x^2+1\right)\left(x^2+2x-1\right)\)
1. Phân tích thành nhân tử
A) x4 + 2x3 + x2
B) x3 - x + 3x2y + 3xy2 + y3 - y
C) 5x2 - 10xy +5y2 - 20z2
2. Phân tích thành nhân tử
A) x2 + 5x -6
B) 5x2 + 5xy - x - y
C) 7x - 6x2 - 2
3.Phân tích thành nhân tử
A) x2 + 4 + 3
B) 2x2 + 3x -5
C) 16x - 5x2 - 3
4. Tìm x, bt
A) 5x ( x - 1 ) = x -1
B) 2( x + 5 ) -x2 - 5x = 0
Bài 2:
a: \(x^2+5x-6=\left(x+6\right)\left(x-1\right)\)
b: \(5x^2+5xy-x-y\)
\(=5x\left(x+y\right)-\left(x+y\right)\)
\(=\left(x+y\right)\left(5x-1\right)\)
c:\(-6x^2+7x-2\)
\(=-6x^2+3x+4x-2\)
\(=-3x\left(2x-1\right)+2\left(2x-1\right)\)
\(=\left(2x-1\right)\left(-3x+2\right)\)
1.
a) \(=x^2\left(x^2+2x+1\right)=x^2\left(x+1\right)^2\)
b) \(=\left(x+y\right)^3-\left(x+y\right)=\left(x+y\right)\left[\left(x+y\right)^2-1\right]\)
\(=\left(x+y\right)\left(x+y-1\right)\left(x+y+1\right)\)
c) \(=5\left[\left(x^2-2xy+y^2\right)-4z^2\right]=5\left[\left(x-y\right)^2-4z^2\right]\)
\(=5\left(x-y-2z\right)\left(x-y+2z\right)\)
2.
a) \(=x\left(x+2\right)+3\left(x+2\right)=\left(x+2\right)\left(x+3\right)\)
b) \(=5x\left(x+y\right)-\left(x+y\right)=\left(x+y\right)\left(5x-1\right)\)
c) \(=-\left[3x\left(2x-1\right)-2\left(2x-1\right)\right]=-\left(2x-1\right)\left(3x-2\right)\)
3.
b) \(=2x\left(x-1\right)+5\left(x-1\right)=\left(x-1\right)\left(2x+5\right)\)
c) \(=-\left[5x\left(x-3\right)-1\left(x-3\right)\right]=-\left(x-3\right)\left(5x-1\right)\)
4.
a) \(\Rightarrow\left(x-1\right)\left(5x-1\right)=0\)
\(\Rightarrow\left[{}\begin{matrix}x=1\\x=\dfrac{1}{5}\end{matrix}\right.\)
b) \(\Rightarrow2\left(x+5\right)-x\left(x+5\right)=0\)
\(\Rightarrow\left(x+5\right)\left(2-x\right)=0\)
\(\Rightarrow\left[{}\begin{matrix}x=-5\\x=2\end{matrix}\right.\)
phân tích đa thức thành nhân tử
a) x2- x- y2- y
b) x2- 2xy- y2-z2
c) 5x- 5y+ 4x- ay
d) 3x3- x2-21x+ 7
e) x3- 4x2- 8x- 8
f) x3- 5x2- 5x+ 1
g) x2y- xz+ z- y
h) x4- x3+ x2- 1
i) x4- x2+ 10x- 25
a: \(x^2-y^2-x-y\)
\(=\left(x-y\right)\left(x+y\right)-\left(x+y\right)\)
\(=\left(x+y\right)\left(x-y-1\right)\)
f: \(x^3-5x^2-5x+1\)
\(=\left(x+1\right)\left(x^2-x+1\right)-5x\left(x+1\right)\)
\(=\left(x+1\right)\left(x^2-6x+1\right)\)
Bài 2 Phân tích thành nhân tử
a) 3x2 – 7x – 10
b) x2 + 6x +9 – 4y2
c) x2 – 2xy + y2 – 5x + 5y’
d) 4x2 – y2 – 6x + 3y
e) 1 – 2a + 2bc + a2 – b2 – c2
f) x3 – 3x2 – 4x + 12
g) x4 + 64
h) x4 – 5x2 + 4
i) (x+1)(x+3)(x+5)(x+7) + 16
j) (x2 + 6x +8)( x2 + 14x + 48) – 9
k) ( x2 – 8x + 15)(x2 – 16x + 60) – 24x2
l) 4( x2 + 15x + 50)(x2 +18x +72) – 3x2
Bài 3 tìm gtnn
A = 9x2 – 6x + 2
B = 4x2 + 5x + 10
C = x2 – x + 10
D = 4x2 + 3x + 20
E = x2 + y2 – 6xy + 10y + 35
F= x2 + y2 – 6x + 4y +2
M= 2x2 + 4y2 – 4xy – 4x – 4y +2021
Bài 2:
a) \(3x^2-7x-10=\left(x+1\right)\left(3x-10\right)\)
b) \(x^2+6x+9-4y^2=\left(x+3\right)^2-\left(2y\right)^2=\left(x+3-2y\right)\left(x+3+2y\right)\)
c) \(x^2-2xy+y^2-5x+5y=\left(x-y\right)^2-5\left(x-y\right)=\left(x-y\right)\left(x-y-5\right)\)
d) \(4x^2-y^2-6x+3y=\left(2x-y\right)\left(2x+y\right)-3\left(2x-y\right)=\left(2x-y\right)\left(2x+y-3\right)\)
e) \(1-2a+2bc+a^2-b^2-c^2=\left(a-1\right)^2-\left(b-c\right)^2=\left(a-1-b+c\right)\left(a-1+b-c\right)\)
f) \(x^3-3x^2-4x+12=\left(x+2\right)\left(x-3\right)\left(x-2\right)\)
g) \(x^4+64=\left(x^2+8\right)^2-16x^2=\left(x^2+8-4x\right)\left(x^2+6+4x\right)\)h) \(x^4-5x^2+4=\left(x+2\right)\left(x+1\right)\left(x-1\right)\left(x-2\right)\)
i) \(\left(x+1\right)\left(x+3\right)\left(x+5\right)\left(x+7\right)+16=\left(x^2+8x+7\right)\left(x^2+8x+15\right)+16=\left(x^2+8x+7\right)^2+8\left(x^2+8x+7\right)+16=\left(x^2+8x+11\right)^2\)
a: \(3x^2-7x-10\)
\(=3x^2+3x-10x-10\)
\(=\left(x+1\right)\left(3x-10\right)\)
b: \(x^2+6x+9-4y^2\)
\(=\left(x+3\right)^2-4y^2\)
\(=\left(x+3-2y\right)\left(x+3+2y\right)\)
c: \(x^2-2xy+y^2-5x+5y\)
\(=\left(x-y\right)^2-5\left(x-y\right)\)
\(=\left(x-y\right)\left(x-y-5\right)\)
a) 3x2−7x−10=(x+1)(3x−10)3x2−7x−10=(x+1)(3x−10)
b) x2+6x+9−4y2=(x+3)2−(2y)2=(x+3−2y)(x+3+2y)x2+6x+9−4y2=(x+3)2−(2y)2=(x+3−2y)(x+3+2y)
c) x2−2xy+y2−5x+5y=(x−y)2−5(x−y)=(x−y)(x−y−5)x2−2xy+y2−5x+5y=(x−y)2−5(x−y)=(x−y)(x−y−5)
d) 4x2−y2−6x+3y=(2x−y)(2x+y)−3(2x−y)=(2x−y)(2x+y−3)4x2−y2−6x+3y=(2x−y)(2x+y)−3(2x−y)=(2x−y)(2x+y−3)
e) 1−2a+2bc+a2−b2−c2=(a−1)2−(b−c)2=(a−1−b+c)(a−1+b−c)1−2a+2bc+a2−b2−c2=(a−1)2−(b−c)2=(a−1−b+c)(a−1+b−c)
f) x3−3x2−4x+12=(x+2)(x−3)(x−2)x3−3x2−4x+12=(x+2)(x−3)(x−2)
g) x4+64=(x2+8)2−16x2=(x2+8−4x)(x2+6+4x)x4+64=(x2+8)2−16x2=(x2+8−4x)(x2+6+4x)h) x4−5x2+4=(x+2)(x+1)(x−1)(x−2)x4−5x2+4=(x+2)(x+1)(x−1)(x−2)
i) (x+1)(x+3)(x+5)(x+7)+16=(x2+8x+7)(x2+8x+15)+16=(x2+8x+7)2+8(x2+8x+7)+16=(x2+8x+11)2(x+1)(x+3)(x+5)(x+7)+16=(x2+8x+7)(x2+8x+15)+16=(x2+8x+7)2+8(x2+8x+7)+16=(x2+8x+11)2
Bài 1: Phân tích các đa thức sau thành nhân tử
a)x2-y2-2x+2y e)x4+4y4
b)x2(x-1)+16(1-x) f)x4-13x2+36
c)x2+4x-y2+4 g) (x2+x)2+4x2+4x-12
d)x3-3x2-3x+1 h)x6+2x5+x4-2x3-2x2+1
a.
$x^2-y^2-2x+2y=(x^2-y^2)-(2x-2y)=(x-y)(x+y)-2(x-y)=(x-y)(x+y-2)$
b.
$x^2(x-1)+16(1-x)=x^2(x-1)-16(x-1)=(x-1)(x^2-16)=(x-1)(x-4)(x+4)$
c.
$x^2+4x-y^2+4=(x^2+4x+4)-y^2=(x+2)^2-y^2=(x+2-y)(x+2+y)$
d.
$x^3-3x^2-3x+1=(x^3+1)-(3x^2+3x)=(x+1)(x^2-x+1)-3x(x+1)$
$=(x+1)(x^2-4x+1)$
e.
$x^4+4y^4=(x^2)^2+(2y^2)^2+2.x^2.2y^2-4x^2y^2$
$=(x^2+2y^2)^2-(2xy)^2=(x^2+2y^2-2xy)(x^2+2y^2+2xy)$
f.
$x^4-13x^2+36=(x^4-4x^2)-(9x^2-36)$
$=x^2(x^2-4)-9(x^2-4)=(x^2-9)(x^2-4)=(x-3)(x+3)(x-2)(x+2)$
g.
$(x^2+x)^2+4x^2+4x-12=(x^2+x)^2+4(x^2+x)-12$
$=(x^2+x)^2-2(x^2+x)+6(x^2+x)-12$
$=(x^2+x)(x^2+x-2)+6(x^2+x-2)=(x^2+x-2)(x^2+x+6)$
$=[x(x-1)+2(x-1)](x^2+x+6)=(x-1)(x+2)(x^2+x+6)$
h.
$x^6+2x^5+x^4-2x^3-2x^2+1$
$=(x^6+2x^5+x^4)-(2x^3+2x^2)+1$
$=(x^3+x^2)^2-2(x^3+x^2)+1=(x^3+x^2-1)^2$
Phân tích các đa thức sau thành nhân tử
a,x4+2x3+3x2+2x+1
b,x4-4x3+2x2+4x+1
c,x4+x3+2x2+2x+4
Bài 1: Phân tích đa thức sau thành nhân tử:
1)x3 + 2x2 - 6x - 27
2)12x3 + 4x2 - 27x - 9
3)x4 - 25x2 + 20x - 4
Bài 2: Phân tích đa thức sau thành nhân tử:
1)x3+2x2-6x-27
2)12x3 +4x2 -27x-9
3)x4 -25x2 +20x -4