Exponential functions are in the form
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. In this equation,
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can be determined by figuring out the "common ratio" or the multiplier: the number that you have to multiply each
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value to get the next
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value. So, what do you have to mulriply
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by to get
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. Or
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by to get
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. Your answer to that question is your
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.
To get your
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, you simply need to find the
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value that corresponds to an
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value of
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. So, from the chart, what
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value corresponds to
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?
Now, just substitute the
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and
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you found into
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and you've got your exponential function.