Question

Phân tích đa thức thành nhân tử

1. x² -x+2

2. x² +6x+7

Answer 1

mk chỉnh đề

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

\(x^2+6x+7=x^2+6x+9-2=\left(x+3\right)^2-2=\left(x+3-\sqrt{2}\right)\left(x+3+\sqrt{2}\right)\)

Answer 2

\(1;x^2-x-2\)

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

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

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

\(2,x^2+6x-7\)

\(=x^2-x+7x-7\)

\(=x\left(x-1\right)+7\left(x-1\right)=\left(x+7\right)\left(x-1\right)\)