Question

8)Quais são as raízes da equação x2 – 5x + 6 =0 1 ponto a) { 2 , 3 } b) { 2 , -3 } c) { -2, -3} d) {-2, 3}

Answer 1

Resposta:

Alternativa a)

Explicação passo-a-passo:

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