Question

Use a fórmula de Braskara resolva Qual é a raiz quadrada de -1

Answer 1

$\mathrm{x=\sqrt{-1}\ \to\ x^2=-1\ \to\ x^2+1=0}\\ \mathrm{a=1\ \ \| \ \ b=0\ \ \|\ \ c=1}\\\\ \textrm{Utilizando a f\'ormula quadr\'atica, teremos que:}\\\\ \mathrm{x=\dfrac{-b\pm\sqrt{b^2-4ac}}{2a}=\dfrac{0\pm\sqrt{0^2-4.1.1}}{2.1}}\\\\ \mathrm{x=\dfrac{\pm\sqrt{-4}}{2}=\dfrac{\pm2i}{2}=\pm i}\ \to\ \boxed{\mathbf{\sqrt{-1}=i}}}$