SOLUTION: Given f(x)= 18/x+4 and g(x)= the cubed root of x find the value of the following compositions a. (g of f)(2) b. (f o f)(1)

Algebra ->  Exponential-and-logarithmic-functions -> SOLUTION: Given f(x)= 18/x+4 and g(x)= the cubed root of x find the value of the following compositions a. (g of f)(2) b. (f o f)(1)      Log On


   

Question 380901: Given f(x)= 18/x+4 and g(x)= the cubed root of x find the value of the following compositions
a. (g of f)(2)
b. (f o f)(1)
Answer by jsmallt9(3758) About Me  (Show Source):
You can put this solution on YOUR website!
f%28x%29+=+18%2F%28x%2B4%29
g%28x%29+=+root%283%2C+x%29
a. (g of f)(2)
First let's find (g of f)(x):
(g of f)(x) = g(f(x)) = g%2818%2F%28x%2B4%29%29+=+root%283%2C+18%2F%28x%2B4%29%29
So (g of f)(2) = root%283%2C+18%2F%28%282%29%2B4%29%29+=+root%283%2C+18%2F6%29+=+root%283%2C+3%29

b. (f o f)(1)
Again, let;s tart with (f o f)(x):
(f o f)(x) = f(f(x)) = f%2818%2F%28x%2B4%29%29+=+18%2F%28%2818%2F%28x%2B4%29%29+%2B+4%29
(f o f)(1) =