# Entering Formulas

Formulas are a way of calculating one cell's entry based on what is in other cells.

You enter a formula in a cell just like you enter other data, by clicking and typing. A formula cell must start with an equals sign so that Excel knows it's a formula. Cell references are used to identify cells in the formula.

Example 1: We can calculate "two times the entry in C4 minus 3 times the entry in D2" and put the result in D5 using the formula =2*C4-3*D2 in cell D5 as shown below:

 A B C D 1 2 2 3 4 7 5 8

Notice that the actual formula doesn't appear in D5, only the result. You can see or edit the formula by clicking on a cell in Excel; the formula will appear in the entry area, as shown in the screenshot below:

## Operations

Excel can carry out all the usual arithmetic operations on cells, plus a lot more. The common symbols Excel uses are listed below:

 Symbol Meaning + plus - minus * times / divided by ^ exponent

You can also use parentheses to group expressions. (When in doubt, use more parentheses!)

Note: the exponential function is not represented using ^. Excel has a special function EXP() to represent the exponential function; see Special Functions for more information.

More Examples:

• To find the square of cell A2, use =A2^2.
• To find the cube of cell C3 and add cell B4 times cell B5, use =C3^3+B4*B5.
• To divide cell B3 by cell B2, use =B3/B2.
• To find the average of cells A2 and A3, use =(A2+A3)/2.