1.3.1a Composite Function Example 1

Example 1
If f : x x + 5 ,   and g : x x 2 + 2 x + 3  , find
(a) the value of gf(2),
(b) the value of fg(2)
(c) the composite functions fg
(d) the composite functions gf
(e) the composite functions g 2
(f) the composite functions f 2



correction for part (c)
fg( x )=f( x 2 +2x+3 )  =( x 2 +2x+3 )+5  = x 2 +2x+3+5  = x 2 +2x+8

correction for part (e)
g 2 ( x )=gg( x ) =g( x 2 +2x+3 ) = ( x 2 +2x+3 ) 2 +2( x 2 +2x+3 )+3 = x 4 +2 x 3 +3 x 2 +2 x 3 +4 x 2 +6x +3 x 2 +6x+9 = x 4 +4 x 3 +10 x 2 +12x+9



2 thoughts on “1.3.1a Composite Function Example 1”

Leave a Comment