a: =(9x^2+6x)/3x=3x+2

b: =(2x^2-4x+x-2)/[-(x-2)]

=-2x-1

a: \(=\dfrac{x\left(x^2+x-2\right)}{x+2}=\dfrac{x\left(x+2\right)\left(x-1\right)}{x+2}=x^2-x\)

b: \(=\dfrac{x^3-3x^2+2x+24}{x+2}=\dfrac{x^3+2x^2-5x^2-10x+12x+24}{x+2}=x^2-5x+12\)

đề thiếu rồi bạn ơi

\(\dfrac{-x^4-3x^2+2x}{x-2}\)

\(=\dfrac{-x^4+2x^3-2x^3+4x^2-7x^2+14x-12x+24-24}{x-2}\)

\(=-x^3-2x^2-7x-12+\dfrac{-24}{x-2}\)

`(-x^4+2x-3x^2):(x-2)`

`=[-x(x^3+3x-2)]:(x-2)`

`=[-x(x^3-2x^2+2x^2-4x+7x-14+12)]:(x-2)`

`={-x[x^2(x-2)+2x(x-2)+7(x-2)]-12x+24-24}:(x-2)`

`=[-x(x-2)(x^2+2x+7)-12(x-2)-24]:(x-2)`

`=-x(x^2+2x+7)-12` và dư `-24`

`=-x^3-2x^2-7x-12` và dư `-24`

\(\dfrac{-x^4-3x^2+2x}{x-2}\)

\(=\dfrac{-x^4+2x^3-2x^3+4x^2-7x^2+14x-12x+24-24}{x-2}\)

\(=-x^3-2x^2-7x-12-\dfrac{24}{x-2}\)

\(=\left(3x^4-3x^3+x^3-x^2+8x^2-8x+9x-9\right):\left(x-1\right)\\ =\left(x-1\right)\left(3x^3+x^2+8x+9\right):\left(x-1\right)\\ =3x^3+x^2+8x+9\)

help me

Vậy \(\left(2x^4+2x^3+3x^2-5x-20\right):\left(x^2+x+4\right)=2x^2-5\)

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

=(3x^3-6x)(3x^2+x-2)

=9x^5+3x^4-6x^3-18x^3-6x^2+12x

=9x^5+3x^4-12x^3-6x^2+12x

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

b: \(\dfrac{A\left(x\right)}{B\left(x\right)}=\dfrac{x^4-\dfrac{1}{2}x^3+\dfrac{1}{2}x^3-\dfrac{1}{4}x^2+\dfrac{9}{4}x^2-\dfrac{9}{8}x-\dfrac{15}{8}x+\dfrac{15}{16}+a-\dfrac{1}{16}}{2x-1}\)

Để A(x) chia hết cho B(x) thì a-1/16=0

hay a=1/16