If #f(x)=3(x+5)+4/x#, what is f(a+2)?

1 Answer
Jan 2, 2017

To determine #f(a+2)# you need to substitute #color(red)(a + 2)# for each occurrence of #x# in the given function. See below for full explanation.

Explanation:

If

#f(color(red)(x)) = 3(color(red)(x) + 5) + 4/color(red)(x)#

Then

#f(color(red)(a + 2)) = 3(color(red)(a + 2) + 5) + 4/color(red)(a + 2)#

Simplifying gives:

#f(color(red)(a + 2)) = 3(a + 7) + 4/(a + 2)#