`@` `\text {Ans}`

`\downarrow`

`4x^3 - 4x^2 - 9x + 9`

`= (4x^3 - 4x^2) - (9x - 9)`

`= 4x^2(x - 1) - 9(x - 1)`

`= (4x^2 - 9)(x - 1)`

____

`x^3 + 6x^2 + 11x + 6`

`= x^3 + x^2 + 5x^2 + 5x + 6x + 6`

`= (x^3 + x^2) + (5x^2 + 5x) + (6x + 6)`

`= x^2*(x + 1) + 5x(x + 1) + 6(x + 1)`

`= (x^2 + 5x + 6)(x+1)`

____

`x^2y - x^3 - 9y + 9x`

`= (x^2y - 9y) - (x^3 - 9x)`

`= y(x^2 - 9) - x(x^2 - 9)`

`= (y - x)(x^2 - 9)`

b: =x^3+x^2+5x^2+5x+6x+6

=(x+1)(x^2+5x+6)

=(x+1)(x+2)(x+3)

c: =x^2(y-x)-9(y-x)

=(y-x)(x^2-9)

=(y-x)(x-3)(x+3)

a: =(4x^3-4x^2)-(9x-9)

=4x^2(x-1)-9(x-1)

=(x-1)(4x^2-9)

=(x-1)(2x-3)(2x+3)

\(\left(x^2-2.\frac{9x}{2}+\left(\frac{9}{2}\right)^2\right)+2-\frac{81}{4}\)

\(\left(x-\frac{9}{2}\right)^2-\frac{73}{4}=\left(x-\frac{9}{2}-\sqrt{\frac{73}{4}}\right)\left(x-\frac{9}{2}+\sqrt{\frac{73}{4}}\right)\)

P/S : h cho chua Pain

\(9x^2-4\left(x-1\right)^2\)

\(=\left[3x+2\left(x-1\right)\right]\left[3x-2\left(x-1\right)\right]\)

\(=\left[3x+2x-2\right]\left[3x-2x+2\right]\)

\(=\left(5x-2\right)\left(x+2\right)\)

Trí làm đúng rồi nha

\(=\left(x^2+2x\right)^2+9\left(x^2+2x\right)+20\)

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

=(x-5)(x-4)

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

\(x^2-9x+20=\left(x^2-4x\right)-\left(5x-20\right)=x\left(x-4\right)-5\left(x-4\right)=\left(x-4\right)\left(x-5\right)\)

\(x^3-9x^2+6x+16\\=x^3+x^2-10x^2-10x+16x+16\\=x^2(x+1)-10x(x+1)+16(x+1)\\=(x+1)(x^2-10x+16)\\=(x+1)(x^2-2x-8x+16)\\=(x+1)[x(x-2)-8(x-2)]\\=(x+1)(x-2)(x-8)\\Toru\)

\(x^3-9x^2+6x+16\)

\(=x^3-8x^2-x^2+8x-2x+16\)

\(=x^2\left(x-8\right)-x\left(x-8\right)-2\left(x-8\right)\)

\(=\left(x^2-x-2\right)\left(x-8\right)\)

\(=\left(x^2+x-2x-2\right)\left(x-8\right)\)

\(=\left(x+1\right)\left(x-2\right)\left(x-8\right)\)

`#3107.101107`

`x^3 - 9x^2 + 6x + 16`

`= x^3 - x^2 - 8x^2 - 2x + 8x + 16`

`= (x^3 - x^2 - 2x) - (8x^2 - 8x - 16)`

`= x(x^2 - x - 2) - 8(x^2 - x - 2)`

`= (x - 8)(x^2 - x - 2)`

`= (x - 8)(x - 2)(x + 1)`

A=\(x^2-9x\)

\(=x\cdot x-x\cdot9\)

=x(x-9)

\(\left(x^2+x\right)^2+9x^2+9x+14\)

= \(\left(x^2+x\right)^2-4+\left(9x^2+9x+18\right)\)

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

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

= \(\left(x^2+x+2\right)\left(x^2+x+7\right)\)

Chúc bạn làm bài tốt!!!!!!

ai giúp mình với . ko bik có sai đề không chứ minh giải miết không ra

cảm ơn bạn nha. VẬy mà minh lại không nghĩ ra chắc là do street

\(\left(x^2-3x+2\right)\left(x^2-9x+20\right)-40=\left(x-1\right)\left(x-2\right)\left(x-4\right)\left(x-5\right)-40\)

\(=\left(x^2-6x+5\right)\left(x^2-6x+8\right)-40\)
Đặt \(t=x^2-6x+5\) thì ta có \(t\left(t+3\right)-40=t^2+3t-40=\left(t+8\right)\left(t-5\right)\)

Suy ra \(\left(x^2-6x+5\right)\left(x^2-6x+8\right)-40=\left(x^2-6x+13\right)\left(x^2-6x\right)=x\left(x-6\right)\left(x^2-6x+13\right)\)