Question

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

Answer 1

`f(a+2)=3a+21+(4)/(a+2)`

Explanation:

If
`f(x)=3(x+5)+(4)/(x)`

Then we have to find f(a + 2)

Now we replace x by (a + 2) in the given expression.

f(a + 2) = 3[(a + 2) + 5] +
`(4)/(a+2)`

= 3(a + 7) +
`(4)/(a+2)`

= 3a + 21 +
`(4)/(a+2)`

So the answer is
`f(a+2)=3a+21+(4)/(a+2)`

Answer 2

`f(x)=3(x+5)+(4)/(x)\\\\\text{substitute x=a+2 to the equation of the function}\\\\f(a+2)=3(a+2+5)+(4)/(a+2)=3(a+7)+(4)/(a+2)=3a+21+(4)/(a+2)`