Err, typing this stuff out is difficult. Here's an example with polynomials: http://en.wikipedia.org/wiki/Big-O_notation#Example . It's images so it's easy to read.
I'm having some trouble with this discrete question:
Find the least natural number n such that
√(x² + x³ + 3) is O(xⁿ).
With the value of n that you have found, is it true that
xⁿ is O( √(x² + x³ + 3) )?
Can anyone help?