Question

Sa se determine solutiile reale ale ecuatiei x patrat -x-2(totu sub radical)=2

Answer 1

$\displaystyle \sqrt{x^2-x-2}=2\Leftrightarrow x^2-x-2=4\Leftrightarrow x^2-x-6=0\\ \\ \left \{ {{x_1+x_2=1} \atop {x_1\times x_2=-6}} \right.\Leftrightarrow \left \{ {{x_1=-2} \atop {x_2=3}} \right. \\ \\ S=\{-2;3\}$