Question

Resolva as equações do segundo grau em IR x²-x-6=0

Answer 1

Oi...

$x^2-x-6=0\\\\Coeficientes:\;a=1,\;b=-1\;e\;c=-6\\\\\Delta=b^2-4ac\\\Delta=-1^2-4\cdot1\cdot(-6)\\\Delta=1+24\\\Delta=25\\\\x=\dfrac{-b\pm\sqrt{\Delta}}{2a}\\\\x=\dfrac{+1\pm\sqrt{25}}{2\cdot1}\\\\x=\dfrac{1\pm5}{2}\\\\x1=\dfrac{1+5}{2}=\dfrac{6}{2}=3\\\\x_2=\dfrac{1-5}{2}=\dfrac{-4}{2}=-2$

Espero ter ajudado