Question

Determine o zero das funções
A)F (x) =-6x+48
B) y=x²-8x+15

Answer 1

Explicação passo-a-passo:

a) $f(x)=-6x+48$

$f(x)=0$

$-6x+48=0$

$-6x+48=0$

$6x=48$

$x=\dfrac{48}{6}$

$x=8$

b) $y=x^2-8x+15$

$y=0$

$x^2-8x+15=0$

$\Delta=(-8)^2-4\cdot1\cdot15$

$\Delta=64-60$

$\Delta=4$

$x=\dfrac{-(-8)\pm\sqrt{4}}{2\cdot1}=\dfrac{8\pm2}{2}$

$x=4\pm1$

$x'=4+1~\Rightarrow~\boxed{x'=5}$

$x"=4-1~\Rightarrow~\boxed{x"=3}$