Question

Aplicando a fórmula de bhaskara, resolva a seguinte equação do segundo grau.

A)$3 {x}^{2} - x - 2 = 0$
me ajudem pfv ​

Answer 1

Resposta:

Explicação passo-a-passo:

$\displaystyle Aplicando~a~f\'{o}rmula~de~Bhaskara~para~3x^{2}-x-2=0~~\\e~comparando~com~(a)x^{2}+(b)x+(c)=0,~temos~a=3{;}~b=-1~e~c=-2\\\\\Delta=(b)^{2}-4(a)(c)=(-1)^{2}-4(3)(-2)=1-(-24)=25\\\\x^{'}=\frac{-(b)-\sqrt{\Delta}}{2(a)}=\frac{-(-1)-\sqrt{25}}{2(3)}=\frac{1-5}{6}=\frac{-4\div2}{6\div2}=-\frac{2}{3}\\\\x^{''}=\frac{-(b)+\sqrt{\Delta}}{2(a)}=\frac{-(-1)+\sqrt{25}}{2(3)}=\frac{1+5}{6}=\frac{6}{6}=1\\\\\\S=\{-\frac{2}{3},~1\}$