if B9 is "01/ 01/ 2001", D3 is "01/ 03/ 2001", D4 is "01/ 04/ 2001" then WORKDAY(B9; 2; D3: D4) returns "Fri Jan 5 2001"
WORKDAY( B9; 2; D3: E4) B9 is "01/ 01/ 2001", D3 is "01/ 03/ 2001", D4 is "01/ 04/ 2003" wurkdei jout "Fri Jan 5 2001"