Question

Resolva a equaçao x² -3x-5=0

Answer 1

Resposta:

$x^2-3x-5=0\quad :\quad x=\frac{3+\sqrt{29}}{2},\:x=\frac{3-\sqrt{29}}{2}$

Explicação passo a passo:

$x^2-3x-5=0\\\\x_{1,\:2}=\frac{-\left(-3\right)\pm \sqrt{\left(-3\right)^2-4\cdot \:1\cdot \left(-5\right)}}{2\cdot \:1}\\\\x_{1,\:2}=\frac{-\left(-3\right)\pm \sqrt{29}}{2\cdot \:1}\\\\x_1=\frac{-\left(-3\right)+\sqrt{29}}{2\cdot \:1},\:x_2=\frac{-\left(-3\right)-\sqrt{29}}{2\cdot \:1}\\\\x=\frac{3+\sqrt{29}}{2},\:x=\frac{3-\sqrt{29}}{2}$