How do I check if a number evaluates to infinity?

Question

I have a series of Javascript calculations that (only under IE) show Infinity depending on user choices.

How does one stop the word Infinity appearing a

Answer 1

Actually n === n + 1 will work for numbers bigger than 51 bit, e.g.

1e16 + 1 === 1e16; // true
1e16 === Infinity; // false