Question

A certain type of cell can double itself every hour, because it has a growth factor of 2. A laboratory has 15 of these cells.

Which function best models the amount of cells in the laboratory after x hours?

f(x)=2^x+15
f(x)=15⋅2^x
f(x)=2⋅15^x
f(x)=15^x+2

Answer 1

Second one

Explanation:

Second choice.

Second one is growing by a factor of 2 because the exponent on 2 tells me that 2 is is being repeated as a factor.

If x=0 then 15*2^0=15(1)=15 which is what we have initially.