Question

  essa primeira parte tem raiz ok $2 x^{2} - x - 1 =1 - x$

Answer 1

$2x^2-x-1=1-x \\ \\ 2x^x-x+x-1-1=0 \\ \\ 2x^2-2=0 \\ \\ 2x^2=2\\\\x^2=2:2 \\ \\ x^2=1 \\ \\ x= \sqrt{1} \\ \\ x'=+1 \\ \\ x''=-1$


S = {1, -1}