The function is .

To find the all zeros of the function, then f(x) = 0.

                         (Substitute f(x) = 0)

                     (The imaginary unit )

The function is .

To find the zeros of the function, then f(x) = 0.

                         (Substitute f(x) = 0)

                    (The imaginary unit )

Using the formula )

The polynomial as a product of linear factors .

The solutions are ; .