Composition of Function

                     Lesson 1

                                                                                                                                                                          

                                                            Problem:   Using f(x)= x + 4, g(x)= 10x Find f(g(x))                                                                                               

                                                            

                                                            Solution    Substitute the expression for function g(10x) in the composition.                 

                                                            Step 1:                                                                                                                                                             

                     

                                                            Solution    Now, substitute this expression (10x) into function f(x)= x + 4 in place of the x- value.

                                                            Step 2:        f(g(x))=f(10x); f(10x)=x+4; f(10x)= 10x+4.                   

                                                                                         

                                                            Solution    Answer: f(g(x))= 10x + 4  

Step 3:                                                             

Complete                                                                   

                                                                                                                               

                                                             Try two practice problems:  

 

                                                                                Solve the following:                                                                                    

 

 Using f(x)=5x - 2 and g(x)= 4x + 3,find:

A.

f(g(4))

 

B.

g(f(5))

 

 

 

 

 

 

 

        

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