About using spreadsheet functions
Functions are predefined formulas that perform calculations by using specific values, called arguments, in a particular order, or structure. For example, the SUM function totals values or ranges of cells, and the PMT function calculates the loan payments based on an interest rate, the length of the loan, and the principal amount of the loan.
Arguments Arguments can be numbers, text, logical values such as TRUE or FALSE, error values such as #N/A, cell references, constants, formulas, or other functions. Each argument you designate must produce a valid value for that argument.
Structure The structure of a function begins with the function name, followed by an opening parenthesis, the arguments for the function separated by commas, and a closing parenthesis. If the function starts a formula, type an equal sign (=) before the function name.
Nested functions
In certain cases, you might need to use a function as one of the arguments of another function. For example, the following formula uses a nested AVERAGE function and compares the result with the value 50.
Valid returns When a nested function is used as an argument, it must return the same type of value that the argument uses. For example, if the argument returns a TRUE or FALSE value, the nested function must return TRUE or FALSE. If it doesn't, the spreadsheet displays a #VALUE! error value.