Is this function correct? (Not a homework Question)

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QuantumPixel
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I was bored and decide to make a function (yes, i am a bit weird). So I came up with this:

f(x)=2x+3
g(f)= f+2
w(g)=g2+3

x=2

f(2)=4+3
f(2)=7
g(7)=7+2
g(7)=9
w(9)=81+3
w(9)=82

Is those working outs correct or not? If it isn't could you tell me where i got it wrong?
 
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As long as you mean g(f(x)) and w(g(f(x))), then you have the right answer
 
Yes, what you have is correct. More generally, with f(x)= 2x+ 3, g(x)= x+ 2, and [itex]w(x)= x^2+ 3[/itex], [itex]g(f(x)= (2x+ 3)+ 2= 2x+ 5[/itex] and [itex]w(g(f(x)))= (2x+ 5)^2+ 3= 4x^2+ 20x+ 28[/itex].

Evaluating that at x= 2 gives 4(4)+ 20(2)+ 28= 16+ 40+ 28= 84.
 
Gackhammer said:
As long as you mean g(f(x)) and w(g(f(x))), then you have the right answer

HallsofIvy said:
Yes, what you have is correct. More generally, with f(x)= 2x+ 3, g(x)= x+ 2, and [itex]w(x)= x^2+ 3[/itex], [itex]g(f(x)= (2x+ 3)+ 2= 2x+ 5[/itex] and [itex]w(g(f(x)))= (2x+ 5)^2+ 3= 4x^2+ 20x+ 28[/itex].

Evaluating that at x= 2 gives 4(4)+ 20(2)+ 28= 16+ 40+ 28= 84.

Thanks for your time on here! :-)

-QuantumPixel