You can put this solution on YOUR website! I imagine you really mean
f(x) = 3^x + 1
As with any unknown function, you are always able to do an x-y value table to give you points to graph...here we have
x -2 -1 0 1 2 3
y 8/9 2/3 1 4 10 28
Graph these and see what kind of curve you get...