Is a formula and a function the same?

Answer 1

An Excel Function is a instruction to excel to perform some built in task or calculation.

E.g. The function SUM(A1:A10) tells Excel to sum up all the values in cells A1, down to A10 and put the result in the cell where you typed it.

A formula is an expression that produces a result and may include functions.

E.g. A1+A2 tells Excel to sum the values in cells A1 and A2 only.

Another example of a formula is A1+SUM(A2:A10)

Both formulas and functions must be preceded by the equals sign for Excel to understand them.
A formula is statement written by the user to be calculated. Formulas can be as simple or as complex as the user wants. A formula can contain values, references to cells, defined names, and functions.

All formulas must start with the equals sign.

=1+2+3

A function is a piece of code designed to calculate specific values and are used inside formulas. Functions to sum values, calculate a trigonometric cosine, and to calculate the current time are built into excel. Additional functions can be defined using Visual Basic.

Functions are typed alongside parenthesizes, where in the arguments if any are listed in between. To use functions in a formula, for example

=COS(3.14) will return the calculated cosine.

=NOW() returns the current time.

=SUM(1+2+3) *2 will multiply the sum by 2
A formula is any equation with a subject; e.g. y = 3x + 4.

A function uses a formula that produces a single value y for every valid subject x.

Answer 2

Sort of... A formula can use a function. A formula is a calculation on a spreadsheet. A function is a pre-defined formula built into Excel.

An example of a function is SUM.

An example of a formula using a function is =SUM(A1:A3).

An example of a formula not using a function is =A5+C5