Question

If f(x)=6 and g(x)=4x+1, find (fog)(x)

Answer 1

The definition

`f(x)=6`

means that f always outputs 6, no matter the input. So, if you want to compute the composition

`(f\circ g)(x)`

It means that you want to compute f giving as input the result of g(x):

`(f\circ g)(x) = f(g(x))`

But no matter the input:
`f(\cdot)` is always 6! So, we have

`(f\circ g)(x) = f(g(x)) = 6`

for every possible x.