Proving a function is continuous for all real numbers This a homework question:

Prove  $f(x) = 2x^3 - 4x^2 + 5$ is continuous for all real numbers.

Which proof technique do I use for this? I don't really know where to start.
Hint: If $f$ and $g$ are continuous, then so are $f + g, f - g, f \cdot g, f / g$ (the later provided $g$ isn't equal to $0$).
As  $f(x)=2x3−4x2+5$ is a polynomial function, it is continuous at every real number (it is a theorem).