Question

URGENTEEE!
Qual as raízes da função f(x) = x² – 16x é 8

Answer 1

Resposta:

x₁ = 15,48

x₂ = 0,51

Explicação passo a passo:

$f\left(x\right)=x^2-16x+8\\\\0=x^2-16x+8\\\\x_{1,\:2}=\frac{-b\pm \sqrt{b^2-4ac}}{2a}\\\\\mathrm{Para\:}\quad a=1,\:b=-16,\:c=8\\\\x_{1,\:2}=\frac{-\left(-16\right)\pm \sqrt{\left(-16\right)^2-4\cdot \:1\cdot \:8}}{2\cdot \:1}\\\\x_{1,\:2}=\frac{16\pm \:\sqrt{256-32}}{2}\\\\x_{1,\:2}=\frac{16\pm \:\:\sqrt{224}}{2}\\\\x_{1,\:2}=\frac{16\pm 14,97}{2}\\\\x_1=\frac{16+14,97}{2}=15,48\\\\x_2=\frac{16-14,97}{2}=0,51$