How do you find the composition of the functions f(x) = 9x^2 and g(x) = x^3, and calculate f(g(x)) = 9x^2 + 9x^5 + 9x^{25} + 9x^{27}?

Finding the Composition of Functions

To find the composition of the functions f(x) = 9x^2 and g(x) = x^3, we follow these steps:

  1. Substitute g(x) into f(x): We need to compute f(g(x)), which means replacing every instance of x in f(x) with g(x).
  2. Given that g(x) = x^3, we can write:
    • f(g(x)) = f(x^3)
  3. Substituting g(x) into f(x):
    • f(x^3) = 9(x^3)^2
    • Now, we simplify this further:
    • f(x^3) = 9x^{6}.

Calculating for Values

The next step is to calculate specific instances as given in the problem:

  • f(g(x)) for the provided expressions:
  • Let’s express it in the format you have mentioned: 9x^2 + 9x^5 + 9x^{25} + 9x^{27}.
  • Each term represents a different value:
  1. For 9x^2, we simply have the original function f(x) = 9x^2 for x = 1. This yields:
    • Result: 9(1)^2 = 9
  2. For 9x^5, we need to evaluate g(x) with x = 1 again:
    • g(1) = (1)^3 = 1 leading to f(g(1)) = f(1) = 9(1)^2 = 9
  3. For 9x^{25}, using the same substitution:
    • g(1) leads to f(g(1)) = 9(1)^{2} = 9
  4. For 9x^{27}, we evaluate:
    • g(1) again gives f(g(1)) = 9

Conclusion

In summary, the function compositions remain consistent across our calculations:

  • f(g(x)) = 9x^{6}
  • For the specific values: 9x^2, 9x^5, 9x^{25}, and 9x^{27}, the simplified results all yield the same consistent outcome: 9.

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