Question

Indique os zeros da função quadrática f(x) = x2 - x – 12

Answer 1

Explicação passo-a-passo:

$\sf x^2-x-12=0$

$\sf \Delta=(-1)^2-4\cdot1\cdot(-12)$

$\sf \Delta=1+48$

$\sf \Delta=49$

$\sf x=\dfrac{-(-1)\pm\sqrt{49}}{2\cdot1}=\dfrac{1\pm7}{2}$

$\sf x'=\dfrac{1+7}{2}~\Rightarrow~x'=\dfrac{8}{2}~\Rightarrow~\red{x'=4}$

$\sf x"=\dfrac{1-7}{2}~\Rightarrow~x"=\dfrac{-6}{2}~\Rightarrow~\red{x"=-3}$

Answer 2

Resposta:

Explicação passo-a-passo:

x^2 -x-12 =0

a= 1

b= -1

c= -12

Δ= $b^{2}$- 4. a . c

Δ= 1 - 4 . 1 .(-12)

Δ= 1+ 48

Δ= 49

x = (-b +- √Δ)/2a

x' = (--1 + √49)/2.1     x'' = (--1 - √49)/2.1

x' = 8 / 2     x'' = -6 / 2

x' = 4     x'' = -3