Syntax. NOT(logical)
Definition. This function reverses the logical value of your argument. Use the NOT() function if you want to incorporate the logical opposite of an expression in a calculation.
Arguments
logical (required). A value or expression that can be evaluated to TRUE or FALSE
Background. If the logical argument is FALSE, the NOT() function returns TRUE. If the logical argument is TRUE, the NOT() function returns FALSE. In the example shown previously, for the FALSE() function, the formula
=(AND(MOD(MONTH(B13),3)=0,DAY(B13)>20)=TRUE)
checked whether the date fell at the end of a quarter, and
=(AND(MOD(MONTH(B13),3)=0,DAY(B13)>20)=FALSE)
checked for days that did not fall at the end of a quarter. You can shorten these conditions:
=(AND(MOD(MONTH(B16),3)=0,DAY(B16)>20))
or
=NOT(AND(MOD(MONTH(B16),3)=0,DAY(B16)>20))
Remember that NOT() is used to query the logical opposite. The shorter formulas take advantage of the fact that =(expression=TRUE) returns the same result as =(expression). The preceding formula could also read
=(NOT(AND(MOD(MONTH(B16),3)=0,DAY(B16)>20))=TRUE)