Question

equação incompleta.
(x+1)² + ( x - 1)² = 10

Answer 1

$(x+1)^2 + ( x - 1)^2 = 10\\\\ x^{2} +x+x+1+ x^{2} -x-x+1=10\to \\\\ 2 x^{2} +2x-2x+2=10\to \\\\ 2 x^{2} =10-2\to \\\\ 2 x^{2} =8\to \\\\ x^{2} = \frac{8}{2} \to\\\\ x^{2} =4\to\\\\ x=\pm \sqrt{4} \to\\\\ x=\pm2\\\\\\ S=(-2;2)$