Question

(x-1)(x^2+5x-2)-x^3+1=0

Answer 1

=>x^3+5x^2-2x-x^2-5x+2-x^3+1=0

=>4x^2-7x+3=0

=>(x-1)(4x-3)=0

=>x=3/4 hoặc x=1

Answer 2

\(\left(x-1\right)\left(x^2+5x-2\right)-x^3+1=0\)

`<=>x^3 + 5x^2 -2x-x^2-5x+2-x^3+1=0`

`<=>4x^2 - 7x +3=0`

`<=> 4x^2 -3x-4x+3=0`

`<=> x(4x-3) - (4x-3)=0`

`<=> (4x-3) (x-1)=0`

\(\Leftrightarrow\left[{}\begin{matrix}4x-3=0\\x-1=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{3}{4}\\x=1\end{matrix}\right.\)