» Simplifying Formulas by Reducing the Complexity of IF Functions

Problem:
The range A2:A4 lists the three primary colors.
To find which of the various colors in column B are primary colors, we could use the following IF formula:
=IF(OR(B2=A2,B2=A3,B2=A4),"Primary Color","Not a Primary Color").
However, such a formula would become increasingly complex as the number of values in column A increases.

Solution:

Use the IF and OR functions as shown in the following Array formula:
{=IF(OR(B2=$A$2:$A$4),"Primary Color","Not a Primary Color")}