Composition of functions (in set)

AI Thread Summary
The discussion revolves around finding the composition of functions f and g, specifically (f o g)(1). The functions are defined with specific mappings, and the user initially struggles to understand the process. After clarification, it is established that g(1) equals 3, leading to the conclusion that f(g(1)) or f(3) also equals 3. The conversation confirms the correct understanding of function composition and the values involved. The final answer is confirmed as 3.
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Homework Statement



A = {0, 1, 2, 3} f and g are functions 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 don't know how to do this..
book just gave me an example but that is totally different from this one.
 
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You know that (f \circ g)(x)=f(g(x))?. Can you tell us what value g(1) has?
 
Last edited:
g(1) would be 3 as g has point (1,3)
 
Ohh i got it.
g(1) is 3 and as f has point (3,3) the answer is 3
thanks!
 
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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