Question

Obter as raízes de 3x²-8x+5=0

Answer 1

Resposta:$Aplicando~a~f\'{o}rmula~de~Bhaskara~para~3x^{2}-8x+5=0~~\\e~comparando~com~(a)x^{2}+(b)x+(c)=0,~temos~a=3{;}~b=-8~e~c=5\\\\\Delta=(b)^{2}-4(a)(c)=(-8)^{2}-4(3)(5)=64-(60)=4\\\\x^{'}=\frac{-(b)-\sqrt{\Delta}}{2(a)}=\frac{-(-8)-\sqrt{4}}{2(3)}=\frac{8-2}{6}=\frac{6}{6}=1\\\\x^{''}=\frac{-(b)+\sqrt{\Delta}}{2(a)}=\frac{-(-8)+\sqrt{4}}{2(3)}=\frac{8+2}{6}=\frac{10\div2}{6\div2}=\frac{5}{3} \\\\S=\{1,~\frac{5}{3} \}$