Question

Responda :

Y= 2x² - 8x + 4

Y= 2x² -8x + 4

f(x) = 2x² + 8x + 4

Y= x² - 5x + 6

Answer 1

f(x)=-2x^2+12x-17

f(x) = 0

-2x^2+12x-17=0

\Delta=12^2-4\cdot(-2)\cdot(-17)=144-136=8

x=\dfrac{-12\pm\sqrt{8}}{2(-2)}=\dfrac{-12\pm2\sqrt{2}}{-4}

x'=\dfrac{-12+2\sqrt{2}}{-4}=\dfrac{-6+\sqrt{2}}{-2}=\dfrac{6-\sqrt{2}}{2}

x"=\dfrac{6+\sqrt{2}}{2}

x = 0

f(0)=-2(0)^2+12(0)-17~~\Rightarrow~~f(0)=-17.

O gráfico passa pelos pontos (\frac{6-\sqrt{2}}{2},0),(\frac{6+\sqrt{2}}{2},0) e (0,-17).

h(x)=x^2+4x+8

f(x) = 0

x^2+4x+8=0

\Delta=4^2-4\cdot1\cdot8=16-32=-16

Não há raízes reais.

x = 0

h(0)=0^2+4(0)+8~~\Rightarrow~~h(0)=8

x_v=\dfrac{-b}{2a}

x_v=\dfrac{-4}{2}=-2

y_v=\dfrac{-\Delta}{4a}

y_v=\dfrac{-(-16)}{4}=4

O gráfico passa pelos pontos (0,8) e (-2,4).