I have all of the working out but i dont understand how the answer works as the roots are where the graph crosses the x axis but f(x) = x^2 + 1 does not cross the x axis can someone please explain.
1. x^2 + 1 =0
2. x^2 = -1
3. square root (x^2) = square root (-1)
4. x = square root (-1)
5. x = + or - i