How do you add/subtract square roots and a non-root?

Question

I'm new to square root addition/subtraction because I haven't done it in a long time, so how do you add or subtract a square root and a non-root? For example, whats 2 + sqrt2? Is the process different if I did 2 + 2sqrt2?

*Edit: radical form, if possible, please. I know how to type these into a calculator and get a decimal. Thanks!

Answer 1

$2+\sqrt2$ is $2+\sqrt2$. There is no nicer or simpler way to write that number exactly.

(If you're working with decimal approximations, then of course $2+\sqrt2$ is $2+1.4142\ldots = 3.4142\ldots$).