Question

determine as raízes da equação 6x² + x - 1= 0? Fórmula de Bhaskara.

Answer 1

$6x^{2}+x-1=0~~~(a=6~~~~~b=1~~~~~c=-1)\\\\\Delta=b^{2}-4ac\\\Delta=1^{2}-4\cdot6\cdot(-1)\\\Delta=1+24\\\Delta=25\\\\x=\dfrac{-b\pm\sqrt{\Delta}}{2a}=\dfrac{-1\pm\sqrt{25}}{2\cdot6}=\dfrac{-1\pm5}{12}$

Então, as raízes da equação são:

$x'=\dfrac{-1+5}{12}=\dfrac{4}{12}=\dfrac{4\div4}{12\div4}=\dfrac{1}{3}\\\\\\x''=\dfrac{-1-5}{12}=-\dfrac{6}{12}=-\dfrac{6\div6}{12\div6}=-\dfrac{1}{2}$