Apple iWork '09 - Manual (Page 316)

LOWER
The LOWER function returns a string that is entirely lowercase, regardless of the case of
the characters in the specified string.
LOWER(source-string)
 source-string: A string. source-string is a string value.
Examples
=LOWER(”UPPER”) returns “upper”.
=LOWER(”Lower”) returns “lower”.
=LOWER(”MiXeD”) returns “mixed”.
Related Topics
For related functions and additional information, see:
“PROPER” on page 317
“UPPER” on page 324
“Listing of Text Functions” on page 306
“Value Types” on page 36
“The Elements of Formulas” on page 15
“Using the Keyboard and Mouse to Create and Edit Formulas” on page 26
“Pasting from Examples in Help” on page 41
MID
The MID function returns a string consisting of the given number of characters from a
string starting at the specified position.
MID(source-string, start-pos, string-length)
 source-string: A string. source-string is a string value.
 start-pos: The position within the specified string at which the action should begin.
start-pos is a number value that must be greater than or equal to 1 and less than or
equal to the number of characters in source-string.
 string-length: The desired length of the returned string. string-length is a number
value and must be greater than or equal to 1.
Usage Notes
If  string-length is greater than or equal to the length of source-string, the string
returned is equal to source-string, beginning at start-pos.
316 Chapter 11 Text Functions