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Composition of Functions

Here's another one we looked at before:

Given f( x ) = x^2 + 3 and g( x ) = x - 2
 

Find

  

( g o f )( x )

  

... which is

  

g( f( x ) )


       1 ) g( blob ) = ( blob ) - 2

       2 ) g( f( x ) ) = ( f( x ) ) - 2

       3 ) g( x^2 + 3 ) = ( x^2 + 3 ) - 2 = x^2 + 1
 

( f o g )( x ) = x^2 - 4x + 7 does not equal x^2 + 1 = ( g o f )( x )

TRY IT:

Given f( x ) = 5x^2 + x and g( x ) = 3x - 1
Find ( g o f )( x )

Look back a couple of pages...

What did you get for ( f o g )( x ) ?