**8/09/2014
**If
*i*
(=√-1) is a root of g(x) = 5x^{4}
– 3x^{3}
+ * a*x

**Scroll
down for the solution.**

**8/09/2014
**Solution.
If
*i*
is root of g(x), then -*i*
is also a root.

Then
g(*i*) = 0 and g(-*i*)
= 0.

Substitute and solve the 2 equations simultaneously, keeping in mind, that:

*i*²
= -1,

*i*³
= -*i*,

and
*i*^{4}
= 1.

**Answer:
**a
= -2, b = -3