Question

4) Encontre as raízes da função f(x)=x² +x -6 URGENTE
x' =-1, x"=2
x'=-3, x"=2
x'=2, x"=3
x' =-1, x" = 3

Answer 1

Resposta:

$x'=-3\\\\x''=2$

Explicação passo a passo:

$f(x)=x^2+x-6$

onde:

$a=1;\\b=1;\\c=-6;$

Pela fórmula de Bháskara:

$x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}\\\\x=\frac{-1\pm\sqrt{1^2-4\cdot1\cdot(-6)}}{2\cdot1}\\\\x=\frac{-1\pm\sqrt{1+24}}{2}\\\\x=\frac{-1\pm\sqrt{25}}{2}\\\\x=\frac{-1\pm5}{2}\\\\x'=\frac{-1-5}{2}=\frac{-6}{2}=-3\\\\x''=\frac{-1+5}{2}=\frac{4}{2}=2$