Question

giúp mình được ko 

 

Answer 1

4: \(x^4-2x^2+1=\left(x^2-1\right)^2=\left(x-1\right)^2\cdot\left(x+1\right)^2\)

13: \(x^2-8x+7=\left(x-7\right)\left(x-1\right)\)

14: \(2x^2-5x+2=\left(x-2\right)\left(2x-1\right)\)

Answer 2

13: Ta có: \(x^2-8x+7\)

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

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

14: Ta có: \(2x^2-5x+2\)

\(=2x^2-4x-x+2\)

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

20: Ta có: \(x^3-5x^2+8x-4\)

\(=x^3-2x^2-3x^2+6x+2x-4\)

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

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