Question

Quais os zeros da função f(x)=x2+x-6?

Answer 1

Determinação dos zeros da função pela fórmula de Bhaskara, observe:

$f(x)=x^{2}+x-6\\\\\\\\\ x = -b~\pm~\dfrac{ \sqrt{b^{2}-4~\cdot~a~\cdot~c}}{2~\cdot~a}}\\\\\\\\\ x = -1~\pm~\dfrac{ \sqrt{1^{2}-4~\cdot~1~\cdot~(-6)}}{2~\cdot~1}}\\\\\\\\ x= -1~\pm~\dfrac{ \sqrt{1+24}}{2}\\\\\\\\ x = -1~\pm~\dfrac{\sqrt{25}}{2}}\\\\\\\\ x = -1~\pm~\dfrac{5}{2}\\\\\\\ x ' = \dfrac{-1+5}{2}}\\\\\\\\ x' = \dfrac{4}{2}\\\\\\\\\ \large\boxed{\boxed{\boxed{x'= 2.}}}}}\\\\\\\\\\ x'' = \dfrac{-1-5}{2}\\\\\\\ x'' = \dfrac{-6}{2}\\\\ \boxed{\boxed{x'' = -3.}}}}$

Ou seja, as raízes dessa função são 2 e -3 respectivamente, espero que te ajude :).