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**skylor****Guest**

Ok I'm having a really hard time understanding this

I'll try to reproduce the graph

x 5 6 7 8 9

f(x) 8 7 5 8 6

g(x) 9 8 7 6 7

find f(g(6))

g(f(7))

f(f(6))

g(g(9))

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 91,418

Hi skylor;

Please read this:

http://www.mathsisfun.com/sets/function … ition.html

f(g(6)) = 8

g(f(7)) = 9

f(f(6)) = 5

g(g(9)) = 7

**In mathematics, you don't understand things. You just get used to them.**

**I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.**

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**John E. Franklin****Member**- Registered: 2005-08-29
- Posts: 3,585

w h(w) j(w)

2 4 1

3 9 1.5

4 16 2

9 81 4.5

16 256 8

j(w) means takeHalfOf(w)

h(w) means square(w)

So j(h(2) = 2 because h(2) = 4 because 2 to the 2 power is 4 and j(4) is half of 4 or 2 back for the answer.

So j(j(j(j(32)=2 because j(32) = 32/2 = 16 and j(16) = 16/2 = 8, and j(8) = 8/2 or 4. and j(4) is 2.

**igloo** **myrtilles** **fourmis**

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