Hi;

atleast showing that they are more or less than 0

An oldie but a goodie.

You get the characteristic polynomial

You can solve for the roots numerically or by graphing but a more precise idea is to use a Sturm chain.

Substitute the endpoints of 0 and infinity.

Count the sign changes. We get 3.

So we get there are 3 roots between 0 and infinity and since 0 is not a root all 3 are greater than 0.

A numerical attack yields:

for the three roots.