Posted by Brenda on Tuesday, September 17, 2013 at 11:42pm.
For given functions f and g find formulas for a)f o g and b)g o f. Simplify results as much as possible. f(x)= x+7/x13 , g(x)= 1/x+1

Math (College PreCal)  Reiny, Wednesday, September 18, 2013 at 12:31am
I will assume that you meant
f(x) = (x+7)/(x13) and g(x) = 1/(x+1)
Those brackets are very critical in this text format.
f o g = f( g(x) )
= (1/(x+1) + 7)/(1/(x+1)  13)
multiply top and bottom by x+1
= (1 + 7(x+1))/)1  13(x+1) )
= (7x + 8)/(13x  12)
or
(7x+8)/(13x  12)
g o f = g( f(x) )
= .....
follow the same steps I used in the first example