Question

X²-2x-3=0 resposta da
equaçao

Answer 1

Resposta:

x'= 3

x''= -1

Explicação passo-a-passo:

x²-2x-3=0

x= -b ± √b²- 4ac / 2a

x= - (-2) ± √4+12 / 2

x= 2 ± √16 / 2

x' = 2 + 4 / 2 = 3

x'' = 2 - 4 / 2 = -1

Answer 2

Resposta:

Explicação passo-a-passo:

$Aplicando~a~f\'{o}rmula~de~Bhaskara~para~x^{2}-2x-3=0~~\\e~comparando~com~(a)x^{2}+(b)x+(c)=0,~temos~a=1{;}~b=-2~e~c=-3\\\\\Delta=(b)^{2}-4(a)(c)=(-2)^{2}-4(1)(-3)=4-(-12)=16\\\\x^{'}=\frac{-(b)-\sqrt{\Delta}}{2(a)}=\frac{-(-2)-\sqrt{16}}{2(1)}=\frac{2-4}{2}=\frac{-2}{2}=-1\\\\x^{''}=\frac{-(b)+\sqrt{\Delta}}{2(a)}=\frac{-(-2)+\sqrt{16}}{2(1)}=\frac{2+4}{2}=\frac{6}{2}=3\\\\S=\{-1,~3\}$