Question

Can somebody explain how to find the answer? I'm confused.

Answer 1

f(5a + 1) =
`(5a+7)/(25a^2+10a+2)`

Explanation:

Given function is,

`f(x)=(x+6)/(x^2+1)`

we have to determine the function when x = (5a + 1)

By substituting the value of x in the given function.

f(5a + 1) =
`((5a+1)+6)/((5a+1)^2+1)`

=
`(5a+7)/((25a^2+10a+1)+1)` [Since (a + b)² = a² + 2ab + b²]

=
`(5a+7)/(25a^2+10a+2)`

Therefore, f(5a + 1) =
`(5a+7)/(25a^2+10a+2)` will be the answer.