Question

$x^{2}$-2x+1=0

Answer 1

$x^{2} -2x+1=0\\\\ a=1;b=-2;c=1\\\\ \Delta=b^2-4ac\to \Delta=(-2)^2-4*1*1\to \Delta=4-4\to \Delta=0\\\\ x'=x''\\\\ x= \frac{-b \pm \sqrt{\Delta} }{2a} \to x= \frac{-(-2) \pm \sqrt{0} }{2*1} \to x= \frac{2 \pm 0 }{2} \to \\\\ x'=x''= \frac{2 }{2} \to x'=x''=1\\\\\\ S=(1)$