You can display the formulas in all cells on a worksheet instead of displaying the actual result. For an example you can read the post Print the formulas in a worksheet.
But what if you want to display the formula instead of the result for just one cell? Excel does not have the built in ability to do this, however placing an apostrophe before your formula will get the job done.
Placing the following formula in a cell with a leading apostrophe:
Will result in the formula to be displayed instead of the result.