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Composition of functions (in set)

  • Thread starter 385sk117
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  • #1
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Homework Statement



A = {0, 1, 2, 3} f and g are fucntions mapping A to A where
f = {(0,1),(1,2),(2,0),(3,3)} and g = {(0,2),(1,3),(2,0),(3,1)}
find

(f o g)(1)

Homework Equations





The Attempt at a Solution



The answer is 3 but i can not get it..
the (1) on the right side means find the y value whem x = 1
I think my (f o g) thing is not correct but i dont know how to do this..
book just gave me an example but that is totally different from this one.
 

Answers and Replies

  • #2
Cyosis
Homework Helper
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You know that [itex](f \circ g)(x)=f(g(x))[/itex]?. Can you tell us what value g(1) has?
 
Last edited:
  • #3
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g(1) would be 3 as g has point (1,3)
 
  • #4
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Ohh i got it.
g(1) is 3 and as f has point (3,3) the answer is 3
thanks!
 
  • #5
Cyosis
Homework Helper
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Yep that is correct. Now what is the value of f(3)?

Edit: Seems you beat me to it! Yes that's all correct.
 

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