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

User Simbolo
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1 Answer

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Answer:

Noting that e^b = 6/a

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.

User Dmitry Vyal
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