How do I avoid repeating long formulas in Excel when working with comparisons?

Question

I know that something like the following

=IF(ISERROR(LONG_FORMULA), 0, LONG_FORMULA)

can be replaced with

=IFERROR(LONG_FOR         


        

Answer 1

Comparing Ln Exp with SQRT ^2:-

because SQRT(0) gives 0 but ln(0) gives #NUM!

So you can choose which one to use depending whether you want the equality or not.

These also work for negative numbers - in theory.