SOLUTION: given that f(x) = x2+x+2 and g(x) = x4-x what are 1. f(g(x)) 2. g(f(x)) 3. f(f(x)) 4. g(g(x)) 5. g(f(g(x)))

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Question 140680: given that f(x) = x2+x+2
and g(x) = x4-x
what are
1. f(g(x))
2. g(f(x))
3. f(f(x))
4. g(g(x))
5. g(f(g(x)))

Answer by stanbon(75887)   (Show Source): You can put this solution on YOUR website!
given that
---------------
f(x) = x^2+x+2
-----------------
g(x) = x^4-x
---------------
what are
1. f(g(x))
= f[x^4-x] = [x^4-x]^2 + [x^4-x] +2
----------------------------------------
2. g(f(x))
= g[x^2+x+2] = [x^2+x+2]^4 -[x^2+x+2]
-----------------------------------------
3. f(f(x))
= f[x^2+x+2] = [x^2+x+2]^2 + [x^2+x+2] + 2
etc.
I hope you can see how these are done.
Cheers,
Stan H.

4. g(g(x))
5. g(f(g(x)))

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