Question

19-2x-15x²=0



pfvv :)​

Answer 1

Olá!

$19 - 2x - 15 {x}^{2} = 0 \: \times ( - 1) \\ - 19 + 2x + 15 {x}^{2} = 0 \\ \\ a = 15 \\ b = 2 \\ c = ( - 19)$

$\Delta = {b}^{2} - 4ac \\ \Delta = {2}^{2} - 4 \times 15 \times ( - 19) \\ \Delta = 4 + 1140 \\ \Delta = 1144$

$x = \frac{ - b \pm \sqrt{\Delta} }{2a} \\ \\ x = \frac{ - 2 \pm \sqrt{1144} }{2 \times 15} \\ \\ x = \frac{ - 2\pm2 \sqrt{286} }{30} \\ \\ x_{1} = \frac{ - 2 + 2 \sqrt{286} }{30} = \frac{ - 1 + \sqrt{286} }{15} \\ \\ x_{2} = \frac{ - 2 - 2 \sqrt{286} }{30} = \frac{ - 1 - \sqrt{286} }{15}$

$S = \{ \frac{ - 1 - \sqrt{286} }{15} , \frac{ - 1 + \sqrt{286} }{15} \}$

Espero ter ajudado! :)