# Math Help - polynomial having real zero...

1. ## polynomial having real zero...

Suppose that $p(x)$ is a polynomial with real coefficients such that for some positive real numbers $c,d$and for all natural numbers $n$ ,we have $c|n|^{3}\leq |p(n)|\leq d|n|^{3}$.
Prove that $p(x)$ has a real zero.

HELP!

2. i think we have to somehow use the concepts of limits
or something like this.....divide the whole inequality by 4,and take the limits tending to infinity