Question

[nguyễn ngọc sơn]

giúp mik vs cảm ơn trước ạ

Answer 1

[Nguyễn Minh Quang]

\(A=\left(\frac{\left(1-x\right)\left(1+x+x^2\right)}{1-x}-x\right):\frac{\left(1-x^2\right)}{\left(1-x^2\right)\left(1-x\right)}\)

\(\Leftrightarrow A=\left(1+x+x^2-x\right):\frac{1}{1-x}=\left(1+x^2\right)\left(1-x\right)\)