You can put this solution on YOUR website! I'm not sure what you're asking. I'm thinking that they want you to find a function for f(g(x)). AKA, they want you to plug in that entire g(x) into the f(x). In other words, they want you to substitute 2x for the x in . That seems kind of funny because you're substituting something for a variable and that already contains the variable. You're probably used to substituting expressions for a variable so that you'll change the old variable in your equation.
In function composition, this is allowed. if we plugged in g(x) into f(x), that's practically replacing the x in f(x) with the g(x)
<---- plugged in g(x) into f(x)
<---- we changed the g(x) to the 2x because we were told that g(x) = 2x
<---- applied rule of exponents that says that the power outside raises everything inside the parentheses/brackets to that power.
<--- Multiplied the 3 and the 4 because we can. This would be your new function rule if they really asked you to find f(g(x)).
NOTE: The equation drawer doesn't align the terms ideally.
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