Phân tích đa thức thành nhân tử:
1/4x2y+5x3-x2y2
5x(x-1)-3y(1-x)
4x2-25
6x-9-x2
X2+4y2+4xy
1/64-27x3
X3-6x2=12x-8
X2-x-y2-y
5x-5y+ax-ay
Phân tích đa thức thành nhân tử
l) 6x2(x – 1) – 9x(x – 1)
m)4x2(x – 2) + 9x(2 – x)
n) 4x2y – 4xy + y
o) 3x(2x – 3y) - 6(3y – 2x)
p) 4x2(x - 1) + (1 – x)
l/ $6x^2(x-1)-9x(x-1)\\=(6x^2-9)(x-1)\\=3(2x^2-3)(x-1)\\=3(\sqrt2 x-\sqrt 3)(\sqrt 2 x+\sqrt 3)(x-1)$
m/ $4x^2(x-2)+9x(2-x)\\=4x^2(x-2)-9x(x-2)\\=(4x^2-9x)(x-2)\\=x(4x-9)(x-2)$
n/ $4x^2y-4xy+y\\=y(4x^2-4x+1)\\=y(2x-1)^2$
o/ $3x(2x-3y)-6(3y-2x)\\=3x(2x-3y)+6(2x-3y)\\=(3x+6)(2x-3y)\\=3(x+2)(2x-3y)$
p/ $4x^2(x-1)+(1-x)\\=4x^2(x-1)-(x-1)\\=(4x^2-1)(x-1)\\=(2x-1)(2x+1)(x-1)$
l)\(6x^2\left(x-1\right)-9x\left(x-1\right)=3x\left(x-1\right)\left(2x-3\right)\)
m) \(4x^2\left(x-2\right)+9x\left(2-x\right)=4x^2\left(x-2\right)-9x\left(x-2\right)=x\left(x-2\right)\left(4x-9\right)\)
n) \(4x^2y-4xy+y=y\left(4x^2-4x+1\right)=y\left(2x-1\right)^2\)
o) \(3x\left(2x-3y\right)-6\left(3y-2x\right)=3x\left(2x-3y\right)+6\left(2x-3y\right)=3\left(2x-3y\right)\left(x+2\right)\)
p) \(4x^2\left(x-1\right)+\left(1-x\right)=4x^2\left(x-1\right)-\left(x-1\right)=\left(4x^2-1\right)\left(x-1\right)=\left(2x-1\right)\left(2x+1\right)\left(x-1\right)\)
Bài 1: Phân tích đa thức thành nhân tử: a) 4y3 + 16y2 + 16y b) 8x2-48x+6xy-36y c) 8x2-48x-6xy+36y d) a2 –2ab+b2 –4 e) 4–x2 –4xy–4y2 f) 8a2 –16a+8ax–16x g) 16–4x2 +8xy–4y2 h) –4x2 –16xy–16y2 Bài 2: Tìm x, biết: a) x3 – 6x2 + 9x = 0 b) 5x(x–6)+3x–18=0 c) 5x(x – 6) – 18 + 3x = 0 d) 5x(x – 6) – 3x + 18 = 0 e) (2x – 3)2 = (5 – x)2 f) (2x + 1)2 = (3x – 2)2 g) 16(2x–3)=-25x2 (3–2x)
b: \(8x^2-48x+6xy-36y\)
\(=8x\left(x-6\right)+6y\left(x-6\right)\)
\(=2\left(x-6\right)\left(4x+3y\right)\)
d: \(a^2-2ab+b^2-4\)
\(=\left(a-b\right)^2-4\)
\(=\left(a-b-2\right)\left(a-b+2\right)\)
phân tích đa thức thành nhân tử (2x-y)(4x2-4xy+y2)-8x2(x-y)
\(\left(2x-y\right)\left(4x^2-4xy+y^2\right)-8x^2\left(x-y\right)\)
\(=\left(2x-y\right)^3-8x^2\left(x-y\right)\)
\(=8x^3-12x^2y+6xy^2-y^3-8x^3+8x^2y\)
\(=-4x^2y-6xy^2-y^3\)
\(=-y\left(4x^2+6xy+y^2\right)\)
Phân tích đa thức thành nhân tử:
a.10x2y – 20xy2 b. x2 – y2 + 10y – 25 c. x2 – y2 + 3x – 3y
d. x3 + 3x2 – 16x – 48 e. 9x3 + 6x2 + x f. x4 + 5x3 + 15x – 9
\(a,10x^2y-20xy^2=10xy\left(x-2y\right)\\ b,x^2-y^2+10y-25=x^2-\left(y^2-10y+25\right)=x^2-\left(y-5\right)^2=\left(x-y+5\right)\left(x+y-5\right)\\ c,x^2-y^2+3x-3y=\left(x-y\right)\left(x+y\right)+3\left(x-y\right)=\left(x-y\right)\left(x+y+3\right)\\ d,x^3+3x^2-16x-48=\left(x^3+3x^2\right)-\left(16x+48\right)=x^2\left(x+3\right)-16\left(x+3\right)=\left(x+3\right)\left(x^2-16\right)=\left(x+3\right)\left(x+4\right)\left(x-4\right)\)
\(e,9x^3+6x^2+x=x\left(9x^2+6x+1\right)=x\left(3x+1\right)^2\\ f,x^4+5x^3+15x-9=\left(x^4+5x^3-3x^2\right)+\left(3x^2+15x-9\right)=x^2\left(x^2+5x-3\right)+3\left(x^2+5x-3\right)=\left(x^2+3\right)\left(x^2+5x-3\right)\)
bài 1 : phân tích đa thức sau thành nhân tử
a)x2 + 4x +4
b)4x2 - 4x + 1
c) 2x- 1 -x2
d) x2+ x +\(\dfrac{1}{4}\)
e)9 - x2
g)(x+5)2 - 4x2
h)(x+1)2 -(2x - 1 )2
i)x2y2 - 4xy +1
k)y2-(x2 - 2x +1 )
l)x3 + 6x2+12x +8
m) 8x3 - 12x2y + 6xy2 - y3
a: \(x^2+4x+4=x^2+2\cdot x\cdot2+2^2=\left(x+2\right)^2\)
b: \(4x^2-4x+1=\left(2x\right)^2-2\cdot2x\cdot1+1^2=\left(2x-1\right)^2\)
c: \(2x-1-x^2\)
\(=-\left(x^2-2x+1\right)=-\left(x-1\right)^2\)
d: \(x^2+x+\dfrac{1}{4}=x^2+2\cdot x\cdot\dfrac{1}{2}+\left(\dfrac{1}{2}\right)^2=\left(x+\dfrac{1}{2}\right)^2\)
e: \(9-x^2=3^2-x^2=\left(3-x\right)\left(3+x\right)\)
g: \(\left(x+5\right)^2-4x^2=\left(x+5+2x\right)\left(x+5-2x\right)\)
\(=\left(5-x\right)\left(5+3x\right)\)
h: \(\left(x+1\right)^2-\left(2x-1\right)^2\)
\(=\left(x+1+2x-1\right)\left(x+1-2x+1\right)\)
\(=3x\left(-x+2\right)\)
i: \(=x^2y^2-4xy+4-3\)
\(=\left(xy-2\right)^2-3=\left(xy-2-\sqrt{3}\right)\left(xy-2+\sqrt{3}\right)\)
k: \(=y^2-\left(x-1\right)^2\)
\(=\left(y-x+1\right)\left(y+x-1\right)\)
l: \(=x^3+3\cdot x^2\cdot2+3\cdot x\cdot2^2+2^3=\left(x+2\right)^3\)
m: \(=\left(2x\right)^3-3\cdot\left(2x\right)^2\cdot y+3\cdot2x\cdot y^2-y^3=\left(2x-y\right)^3\)
GIÚP MK VS
Bài 1 : Phân tích đa thức thành nhân tử
a) x2-6x-y2+9
b) 25-4x2-4xy -y2
c) x2+2xy+y2- xz-yz
d) x2-4xy+4y2-z2+4tz-4t2
Bài 2 : Phân tích đa thức thành nhân tử
a) ax2+cx2-ay+ay2-cy+cy2
b) ax^2+ay^2-bx^2-by^2+b-a
c) ac^2-ad-bc^2+cd+bd-c^3
Bài 3 : Tìm x
a) x(x-5)-4x+20=0
b) x(x+6)-7x-42=0
c) x^3-5x^2+x-5=0
d) x^4-2x^3+10x2-20x=0
1. Phân tích thành nhân tử
a) x2 + 7x + 10; b) x2 – 21x + 110; c) 3x2 + 12x + 9; d) 2ax2 - 16ax + 30a.
2. Phân tích thành nhân tử
a) x2 + x – 6; b) x2 – 2x – 15; c) 4x2 - 12x - 160; d) 5x2y - 10xy - 15y.
3. Phân tích thành nhân tử
a) x2 – xy – 20y2 ; b) 3x4 + 6x2y2 – 45y4 ; c) 2bx2 – 4bxy - 70y2
4. Giải phương trình
a) x2 + x = 72; b) 3x2 – 6x = 24 c) 5x3 – 10x2 = 120x.
5. Phân tích thành nhân tử
a) 3x2 -11x + 6; b) 8x2 + 10x – 3 ; c) 8x2 -2x -1 .
Dạng 1: Phân tích đa thức sau thành nhân tử 1) x ^ 2 - 9 2) 5x - 5y + ax - ay 3) x ^ 2 + 6x + 9 4) 10x * (x - y) - 7y * (y - x) 5) 5x - 15y 6) x ^ 2 - 2xy + y ^ 2 - z ^ 2
\(1,=\left(x-3\right)\left(x+3\right)\\ 2,=\left(x-y\right)\left(5+a\right)\\ 3,=\left(x+3\right)^2\\ 4,=\left(x-y\right)\left(10x+7y\right)\\ 5,=5\left(x-3y\right)\\ 6,=\left(x-y\right)^2-z^2=\left(x-y-z\right)\left(x-y+z\right)\)
Bài 1: Phân tích các đa thức sau thành nhân tử
a. 1 - 4x2
b. 8 - 27x3
c. 27 + 27x + 9x 2 + x3
d. 2x3 + 4x2 + 2x
e. x2 - 5x - y2 + 5y
f. x2 - 6x + 9 - y2
g. 10x (x - y) - 6y(y - x)
h. x2 - 4x - 5
i. x4 - y4
Bài 2: Tìm x, biết
a. 5(x - 2) = x - 2
b. 3(x - 5) = 5 - x
c. (x +2)2 - (x+ 2) (x - 2) = 0
Bài 3: Tìm giá trị nhỏ nhất của biểu thức
a. A = x2 - 6x + 11
b. B = 4x2 - 20x + 101
c. C = -x2 - 4xy + 5y2 + 10x - 22y + 28
a.
\(1-4x^2=\left(1-2x\right)\left(1+2x\right)\)
b.
\(8-27x^3=\left(2\right)^3-\left(3x\right)^3=\left(2-3x\right)\left(4+6x+9x^2\right)\)
c.
\(27+27x+9x^2+x^3=x^3+3.x^2.3+3.3^2.x+3^3\)
\(=\left(x+3\right)^3\)
d.
\(2x^3+4x^2+2x=2x\left(x^2+2x+1\right)=2x\left(x+1\right)^2\)
e.
\(x^2-y^2-5x+5y=\left(x-y\right)\left(x+y\right)-5\left(x-y\right)\)
\(=\left(x-y\right)\left(x+y-5\right)\)
f.
\(x^2-6x+9-y^2=\left(x-3\right)^2-y^2=\left(x-3-y\right)\left(x-3+y\right)\)
g. 10x(x-y)-6y(y-x)
=10x(x-y)+6y(x-y)
=(x-y)(10x+6y)
h.x2-4x-5
=(x-5)(x+1)
i.x4-y4 = (x2-y2)(x2+y2)
B2.
a.5(x-2)=x-2
⇔5(x-2)-(x-2)=0
⇔4(x-2)=0
⇔x=2
b.3(x-5)=5-x
⇔3(x-5)+(x-5)=0
⇔4(x-5)=0
⇔x=5
c.(x+2)2-(x+2)(x-2)=0
⇔(x+2)[(x+2)-(x-2)]=0
⇔4(x+2)=0
⇔x=-2