Question

Find a function where f(0)=2 and f(1)=2

Answer 1

Do you want to be extremely boring?

Since the value is 2 at both 0 and 1, why not make it so the value is 2 everywhere else?

`f(x) = 2` is a valid solution.

Want something more fun? Why not a parabola?
`f(x)= ax^2+bx+c`.

At this point you have three parameters to play with, and from the fact that
`f(0)=2` we can already fix one of them, in particular
`c=2`. At this point I would recommend picking an easy value for one of the two, let's say
`a= 1` (or even
`a=-1`, it will just flip everything upside down) and find out b accordingly:
`f(1)=2 \rightarrow 1^2+b+2=2 \rightarrow b=-1`

Our function becomes

`f(x) = x^2-x+2`

Notice that it works even by switching sign in the first two terms:
`f(x) = -x^2+x+2`

Want something even more creative? Try playing with a cosine tweaking it's amplitude and frequency so that it's period goes to 1 and it's amplitude gets to 2:
`f(x) = A cos (kx)`

Since cosine is bound between -1 and 1, in order to reach the maximum at 2 we need
`A= 2`, and at that point the first condition is guaranteed; using the second to find k we get
`2= 2 cos (k1) = cos k = 1 \rightarrow k = 2\pi`

`f(x) = 2cos(2\pi x)`

Or how about a sine wave that oscillates around 2? with a similar reasoning you get

`f(x)= 2+sin(2\pi x)`

Sky is the limit.