(y²+y)+(-xy-x) = y(y+1)-x(y+1) = (y-x)(y+1)

Lỗi?

Dấu nhân hay dấu cộng( trừ vậy bạn).

\(x^2+3x-4\)

\(=x^2+3x+\frac{9}{4}-\frac{25}{4}\)

\(=\left(x+\frac{3}{2}\right)^2-\left(\frac{5}{2}\right)^2\)

\(=\left(x+4\right)\left(x-1\right)\)

dấu nhân ấy. Nhìn rõ mà

\(x^5-1=\left(x-1\right)\left(x^4+x^3+x^2+x+1\right)\)

- Đúng thì k hộ tớ nhé ^^

= \(5x^3-2x^2-10x^2+4x+10x-4\)

= \(5x^2\left(x-\frac{2}{5}\right)-10x\left(x-\frac{2}{5}\right)+10\left(x-\frac{2}{5}\right)\)

=\(\left(x-\frac{2}{5}\right)\left(5x^2-10x+10\right)\)

Chuc ban hoc tot!

Áp dụng hằng đẳng thức hiệu 2 bình phương .

\(4x^2-3y^2\)

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

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

_ Chúc bạn học tốt _

`n)x^2+4x+3`

`=x^2+3x+x+3`

`=x(x+3)+(x+3)`

`=(x+3)(x+1)`

`b)x^2+6x+8`

`=x^2+4x+2x+8`

`=x(x+4)+2(x+4)`

`=(x+4)(x+2)`

`->` tách ra nha bạn

\(10,\\ a,x^2-6x+5\\ =x^2-x-5x+5\\ =x\left(x-1\right)-5\left(x-1\right)\\ =\left(x-1\right)\left(x-5\right)\)

\(b,x^2+6x+8\\ =x^2+4x+2x+8\\ =x\left(x+4\right)+2\left(x+4\right)\\ =\left(x+4\right)\left(x+2\right)\)

\(c,2x^2+10x+8\\ =2\left(x^2+5x+4\right)\)

\(d,x^2-5x+14\)

`->` Có đúng đề không cậu nhỉ ?

\(e,x^2-7x+10\\ =x^2-2x-5x+10\\ =x\left(x-2\right)-5\left(x-2\right)\\ =\left(x-2\right)\left(x-5\right)\)

\(g,3x^2-5x-2\\ =3x^2+x-6x-2\\ =x\left(3x+1\right)-2\left(3x+1\right)\\ =\left(3x+1\right)\left(x-2\right)\)

\(h,2x^2+x-6\\ =2x^2+4x-3x-6\\ =2x\left(x+2\right)-3\left(x+2\right)\\ =\left(x+2\right)\left(2x-3\right)\)

\(i,x^2-9x+18\\ =x^2-3x-6x+18\\ =x\left(x-3\right)-6\left(x-3\right)\\ =\left(x-3\right)\left(x-6\right)\)

\(k,2x^2-6x+9\)

`->` Cậu xem lại đề 

\(e,3x^2-5x-2\\=3x^2+x-6x-2\\ =x\left(3x+1\right)-2\left(3x+1\right)\\ =\left(3x+1\right)\left(x-2\right)\)

`m,` \(x^2-5+6\)

`->` Cậu xem lại đề 

Đề sai nhé .Sửu lại

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

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

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

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

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

\(=9a^2b^2\left(2a-b\right)\)

18a³b² - 9a²b³

9a²b²(2a-b)

9a²b².(2a - b)