**Problem : **
Find all roots, real and complex, of the following polynomial:
*x*
^{2} + 4
.

**Problem : **
Find all roots, real and complex, of the following polynomial:
*x*
^{4} - *x*
^{3} - *x*
^{2} - *x* - 2
.

**Problem : **
If
3ı
is a root of a polynomial, what must one other root be?

**Problem : **
Find all roots, real and complex, of the following polynomial:
*x*
^{3} +4*x*
^{2} + 25*x* + 100
.

**Problem : **
Find all roots, real and complex, of the following polynomial:
*x*
^{4} +2*x*
^{2} - 3
.

**Problem : **
Find all roots, real and complex, of the following polynomial:
*x*
^{8} +2*x*
^{7} +4*x*
^{6} +8*x*
^{5} - *x*
^{4} -2*x*
^{3} -4*x*
^{2} - 8*x*
.