Answer 1

`a,(x-1)(x^2-2)=0`

$\to \left[ \begin{array}{l}x=1\\x^2=2\end{array} \right.$

$\to \left[ \begin{array}{l}x=1\\x=-\sqrt{2}\\x=\sqrt{2}\end{array} \right.$

`b,(3x-1)(2x-5)=(3x-1)(x+2)`

`=>(3x-1)(2x-5-x-2)=0`

`=>(3x-1)(x-7)=0`

$\to \left[ \begin{array}{l}x=7\\x=\dfrac{1}{3}\end{array} \right.$

`c,2x^3+5x^2-3x=0`

`=>x(2x^2+5x-3)=0`

`=>x(2x^2+6x^2-x-3)=0`

`=>x[2x(x+3)-(x+3)]=0`

`=>x(2x-1)(x+3)=0`

$\to \left[ \begin{array}{l}x=0\\x=-3\\x=\dfrac{1}{2}\end{array} \right.$