Exponential function for 2,6,18,54

For this case we have a function of the form:

y = A * (b) ^ x

Where,

A: initial amount

b: growth rate

x: domain of the function.

We have then that the function is:

y = 2 * (3) ^ x

For example,

for x = 0:

y = 2 * (3) ^ 0

y = 2

for x = 1:

y = 2 * (3) ^ 1

y = 6

for x = 2:

y = 2 * (3) ^ 2

y = 18

for x = 3:

y = 2 * (3) ^ 3

y = 54

Answer:

y = 2 * (3) ^ x