WEBVTT
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for this problem. We have the graph of y
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equals log based two of X, and I've made
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a rough sketch of it. We know it goes
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through the X axis at the 20.10 and we're interested
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in finding out what its X corn it is.
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When the Y coordinate is three feet, every unit
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is one inch, so three feet will be 36
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inches. So what is the X coordinate when the
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Y coordinate is 36 inches? How far out would
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we have to go? Well, what we can
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do is take our function log based two of X
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and set it equal to 36. Substitute 36 in
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for why and when we saw that we get X
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equals two to the 36th Power. Now, if
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you put that in your calculator, you get a
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very, very large number. It's it changes it
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to scientific notation. I can only write part of
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its 6.87 times 10 to the 10th inches. Now
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let's convert that into miles, so it'll be easier
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to manage. So to convert it into feet,
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we would divide it by 12. Now we have
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feet and to convert it to Miles. We would
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divide that by 5280 because there are 5280 feet in
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a mile, and once we divide by both of
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those numbers, we end up with one million 84,000
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587 0.7 miles. That's how far you would have
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to go to reach a height of three feet on
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this graph. That is pretty extreme. That shows
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us just how slowly this graph is growing.