Unformatted text preview: A map fig - T is injecttre or one-to-one
"If for a x x, es whenever x, 7x2
then who fixis / f ( xz ) ."
In other words, a graph is one-to-one
if it passes the horizontal time test .
I may Is surjective if it's image f (5) = T;
if for bry y CT there exists in & ES sick that
F ( x ) = 4. Those chements X E S with
F-( 2):y are inverse images of y.
In other words, a graph is surjective
if every I has its y according to fo and
* Breckin means the graph is both injecting
and it passes the horizontal hime lest.
( 9 0 f ) ( x ) : 5 9 ( f ( x ) )
( q o f ] ( ) * ( fog ) ( x )
Invertible functions - find them by
switching y and x. If it's a parable
it needs to restricted....
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- Fall '08
- Composition, Bijective, Surjective, Injective, Invertible Functions