Question

Se considera ecuatia 2x^2 +ax+b=0, unde a si b sunt nr naturale. a) pentru a=3 si b=1, rezolvati ecuatia in multimea nr reale

Answer 1

$2 {x}^{2} + 3x + 1 = 0$

$c = 2$

$a = 3$

$b = 1$

$\Delta = {a}^{2} - 4cb$

$\Delta = {3}^{2} - 4 \times 2 \times 1$

$\Delta = 9 - 8$

$\Delta = 1$

$x_{1,2}=\frac{-a\pm\sqrt{\Delta}}{2c}$

$x_{1,2}=\frac{-3\pm\sqrt{1}}{2 \times 2}$

$x_{1,2}=\frac{-3\pm1}{4}$

$x_{1}=\frac{-3 + 1}{4}$

$x_{1}=\frac{-2}{4}$

$x_{1}= - \frac{1}{2}$

$x_{2}=\frac{-3 - 1}{4}$

$x_{2}=\frac{-4}{4}$

$x_{2}= - 1$