`(x-1)^2 - [1-(x-1)] = 0`
`<=>x^2-2x+1- 1+x-1 = 0`
`<=>x^2-x-1 = 0`
`<=>x^2-2*1/2x+(1/2)^2-5/4 = 0`
`<=>(x-1/2)^2-5/4 = 0`
`<=>(x-1/2)^2 = 5/4`
`<=>`\(\left[ \begin{array}{l}x-\dfrac{1}{2}=\sqrt{\dfrac{5}{4}}\\x-\dfrac{1}{2}=-\sqrt{\dfrac{5}{4}}\end{array} \right.\) `<=>`\(\left[ \begin{array}{l}x=\sqrt{\dfrac{5}{4}}+\dfrac{1}{2}\\x=-\sqrt{\dfrac{5}{4}}+\dfrac{1}{2}=\dfrac{1}{2}-\sqrt{\dfrac{5}{4}}\end{array} \right.\)
`<=>x={sqrt(5/4)+1/2;1/2-sqrt(5/4)}`
