One to One= A function 1  5 2 6 3  7 4 8  5 9   The Rule is ‘ADD 4’

Not a function Paris Ahmed  London Peter Dubai Ali  New York Jaweria Cyprus Ahmed Peter Ali Jaweria Hamad     Has Visited There are MANY arrows from each person and each place is related to MANY People. It is a MANY to MANY relation.

FUNCTION       Person Has A Mass of Kg Bilal 62 Peter Salma 64 Alaa George Aziz 62 64 66      In this case each person has only one mass, yet several people have the same Mass. This is a MANY to ONE relationship

Not a function Is the length of cm object  Pen Pencil Ruler Needle Stick  14 30    Here one amount is the length of many objects. This is a ONE to MANY relationship

FUNCTIONS Many to One Relationship One to One Relationship

Function - Domain and Range! x2x+1 A B 1 2 3 4 1 3 5 7 9 Domain Range

Which Are Functions? (b) (a) (c) (d) (a) and (c)

Which Are Functions? (b) (a) (c) (d) (a) and (c)