Question

Which of the following exponential functions goes thru points (1,6) and (2,12)

Answer 1

Answer:

Noting that e^b = 6/a

Step-by-step explanation:

Use the general expo function y = ae^(bx).

Subbing 6 for y and 1 for x, we get  6 = ae^(b), or   e^b = 6/a.

Subbing 12 for y and 2 for x, we get   12 = ae^(2b), or 12/a = (e^b)²

Now let's find the value of the coefficient a.  Noting that e^b = 6/a, rewrite

12/a = (e^b)² as 12/a = (6/a)².

Dividing both sides by 6/a, we get 2 = 6/a, or a = 3.

Again Noting that e^b = 6/a, e^b = 6/3, or e^b = 2.

Taking the natural log of both sides, we get b = ln 2.

Then our y = ae^(bx) becomes:

                y = 3e^(ln 2·x), or   y = 3·2^x

Note:  next time, please share the answer choices.  Thank you.