I'm attempting to create a table with these values y=3x,y=3x^2, and y=3^x

With values of X from 0to5. Below, i have an example of what I'm trying to achieve, though with these functions. Hopefully, someone can help me understand the difference in values with these functions.

Any help is appreciated

Y=2x

X Y First difference

0 0

1 2 2-0=2

2 4 4-2=2

3 6 6-4=2

4 8 10-8=2

5 10 12-8=2

6 12 12-10=2