SOLUTION: If f(x) = x + 5 and g(x) = 6x, then what is g(f)(x) -- that is, what is the value of the composite function, where we start with function f and end with function g -- if our starti

Algebra ->  Functions -> SOLUTION: If f(x) = x + 5 and g(x) = 6x, then what is g(f)(x) -- that is, what is the value of the composite function, where we start with function f and end with function g -- if our starti      Log On


   

Question 988248: If f(x) = x + 5 and g(x) = 6x, then what is g(f)(x) -- that is, what is the value of the composite function, where we start with function f and end with function g -- if our starting input is 3?
Answer by vleith(2983) About Me  (Show Source):
You can put this solution on YOUR website!
To find g((f(x)) substitute the value for f(x) into g(x) everywhere
you are told f(x) = x+5
So substitute (x+5) for x everyplace it shows up in g(x)
g%28x%29+=+6x
g%28f%28x%29%29+=+6%2A%28f%28x%29%29
+g%28f%28x%29%29+=+6%2A%28x%2B5%29
g%28f%28x%29%29+=+6x+%2B+30
Now it is easy to find g(f(x)) when x = 3. Just plug in 3 for x and simplify.
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