Question 171486
the denominator cannot be equal to zero or the results will be undefined.....so set the denominator equal to zero and solve
:
{{{x^2+16=0}}}
:
{{{x^2=-16}}}

so the only restricted values are complex numbers.....all real numbers solutions will work in this equation.

to be specific x={{{sqrt(-16)}}}={{{sqrt(-1(16))}}}={{{4i}}}