bạn ko ghi yêu cầu sao mik trả lời dc

x^3-2x^2-4xy^2+x

=x(x^2-2x-4y^2+1)

=x[(x^2-2x+1)-4y^2]

=x[(x-1)^2-4y^2]

=x(x-1-2y)(x-1+2y)

Phân tích đa thức thành nhân tử 

x³-2x²-4xy²+x

= x (x²-2x-4y²+1)

1:Electricity helps children  to study better, and paved roads make transportation easier.

2:Villagers in the Southern  usually live in houses which built on stilts to keep above flood waters.

3:Public works have helped local people especially Khmer people to develop production , reduce poverty and create better lives .

4:Agricultural work is becoming  less difficult thanks to the machine.

5:Along the  coastal lines , fishermen  depend on the  sea to live on.

6:They  live in  a small community near  a temple  where great events  such as festivals are organized.

7:People in  Central Highlands and northern regions live by  growing rice, rubber trees, coffee and tea.​​

dốt nó

Lấy lá cây giã nát hòa với một chút nước và vắt lấy nước cốt bỏ bã sau đó hòa thêm chút muối rồi để trong tủ lạnh khi nào dùng thì lấy ra dùng bình phun phun vào nơi có muỗi hoặc phun lên cánh quạt để quạt hương đi khắp phòng

1.Why did you have to go to the hospital?
2.Why do you have to get up early tomorrow?
3.Where does Lan have to go?
4.How long do you have to wait?
5.Why do you have to phone your sister?

a) \(x^3+x^2y-x^2z-xyz\)

\(=x^2\left(x+y\right)-xz\left(x+y\right)\)

\(=\left(x+y\right)\left(x^2-xz\right)\)

\(=x\left(x+y\right)\left(x-z\right)\)

b) \(x^2-6x+9-9y^2\)

\(=\left(x^2-2\cdot x\cdot3+3^2\right)-\left(3y\right)^2\)

\(=\left(x-3\right)^2-\left(3y\right)^2\)

\(=\left(x-3-3y\right)\left(x-3+3y\right)\)

c) \(x^2+9x+20\)

\(=x^2+5x+4x+20\)

\(=x\left(x+5\right)+4\left(x+5\right)\)

\(=\left(x+5\right)\left(x+4\right)\)

d) \(x^4+4\)

\(=\left(x^2\right)^2+2\cdot x^2\cdot2+4-2\cdot x^2\cdot2\)

\(=\left(x^2+2\right)-\left(2x\right)^2\)

\(=\left(x^2-2x+2\right)\left(x^2+2x+2\right)\)

a/\(x^3+x^2y-x^2z-xyz\)

\(=\left(x^3-x^2y\right)+\left(x^2y-xyz\right)\)

\(=x^2\left(x-z\right)+xy\left(x-z\right)\)

\(=\left(x-z\right)\left(x^2+xy\right)\)

b/\(x^2-6x+9-9y^2\)

\(=\left(x^2-6x+9\right)-9y^2\)

\(=\left(x-3\right)^2-\left(3y\right)^2\)

\(=\left(x-3+3y\right)\left(x-3-3y\right)\)

c/\(x^2+9x+20\)

\(=x^2+4x+5x+20\)

\(=\left(x^2+4x\right)+\left(5x+20\right)\)

\(=x\left(x+4\right)+5\left(x+4\right)\)

\(=\left(x+5\right)\left(x+4\right)\)

d/\(x^4+4\)

\(=x^4+4x^2-4x^2+4\)

\(=\left(x^2+4x^2+4\right)-4x^2\)

\(=\left(x+2\right)^2-\left(2x\right)^2\)

\(=\left(x+2-2x\right)\left(x+2+2x\right)\)