Question

f:R->R , f(x)={ x ^2 +3x+2 }
Determinati numerele reale x pentru care f(x)=2

Answer 1

                   
$x^{2} +3x+2=2 \\ \\ x^{2} +3x+2-2=0 \\ \\ x^{2} +3x=0 \\ \\ x(x+3) = 0 \\ x_1 = 0 \\ x_2 = -3 \\ \\ Verificare: \\ 0^{2} +3*0+2= 0+0+2=2 \\ (-3)^{2} +3*(-3)+2= 9 - 9 + 2 = 0 + 2 = 2$