Question

Considerando a equação

x2 − x− 12, determine:

a) os coeficientes;

b) o discriminante;

c) as raízes.​

Answer 1

x²-x-12

a) a=1

b= -1

c= -12

b) ∆=b²-4ac

∆= (-1)²-4.1.(-12)

∆= 1+ 48

∆= 49

c) x1=

$\frac{ - b + \sqrt{delta} }{2a} = \frac{ - ( - 1) + \sqrt{49} }{2.1} = \frac{1 + 7}{2} = \frac{8}{2} = 4$

x2=

$\frac{ - b - \sqrt{delta} }{2a} = \frac{ - ( - 1) - \sqrt{49} }{2.1} = \frac{1 - 7}{2} = \frac{ - 6}{2} = - 3$