Question

[Linh Nhi]

Thực hiện phép tính :

b) (x³ - 4x² + x + 6) : ( x - 2)

Answer 1

[ღᏠᎮღ🅼🅸🅽🅷ঔ🅽🅶ụ🆈ঌ__[ᴅʀᴇᴀм тᴇᴀм]__]

Mk làm chi tiết từng bc một nên hơi dài 

~ học tốt ~

\(\frac{x^3-4x^2+x+6}{x-2}\)

\(=\frac{x^3-2x^2-2x^2+x+6}{x-2}\)

\(=\frac{\left(x^3-2x^2\right)-\left(2x^2-x-6\right)}{x-2}\)

\(=\frac{x^2\left(x-2\right)-\left(2x^2-4x+3x-6\right)}{x-2}\)

\(=\frac{x^2\left(x-2\right)-[\left(2x^2-4x\right)+\left(3x-6\right)]}{x-2}\)

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

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

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

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

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

\(=\frac{\left(x-2\right)[x\left(x-1\right)-3\left(x-1\right)}{x-2}\)

\(=\frac{\left(x-2\right)\left(x-1\right)\left(x-3\right)}{x-2}\)

\(=\left(x-1\right)\left(x-3\right)\)

Answer 2

[Trần Thùy Dương]

\(\frac{x^3-4x^2+x+6}{x-2}\)

\(=\frac{x^3-2x^2-2x^2+x+6}{x-2}\)

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

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

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

@TrầnMinhPhong.

Đến đoạn này là được rồi .