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| Question 1106851:  Find f(x) and g(x) so that the function can be described as y = f(g(x)).
 y = three divided by square root of quantity three x plus four.
 y= 3/sqrt(3x+4)
 Answer by greenestamps(13209)
      (Show Source): 
You can put this solution on YOUR website! 
 Think of how you would evaluate the expression for a particular value of x:
 (1) multiply by 3
 (2) add 4
 (3) take the square root
 (4) divide 3 by the result
 
 To write the whole expression as a composition of two functions, you can break the steps into two parts any way you want.
 
 solution #1:
 g(x) = multiply by 3 and add 4;
 f(x) = take the square root and divide 3 by the result
 answer #1: g(x) = 3x+4; f(x) = 3/sqrt(x)
 
 solution #2:
 g(x) = multiply by 3, add 4, and take the square root
 f(x) = divided 3 by the result
 answer #2: g(x) = sqrt(3x+4); f(x) = 3/x
 
 solution #3:
 g(x) = multiply by 3
 f(x) = add 4, take the square root, and divide 3 by the result
 answer #3: g(x) = 3x; f(x) = 3/sqrt(x+4)
 
 Solution #4: You could even do something like this, combining all the steps into one of the functions -- although I don't see that it would ever be useful:
 g(x) = 3/sqrt(3x+4); f(x) = x
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