WEBVTT
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this question proposes a sequence that goes one Hey,
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a squared, a cubed all the way up to
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eight to the end and we're told that n is
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an even number. So since N is even,
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what does that mean? Well, that means that
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we're gonna have a total odd number in our sequence
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, right? Look at this. When a is
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in, is to we have uneven number for end
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and we have three numbers in our sequences. Three
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numbers are sequence. If End was four, then
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we'd have five numbers in our sequence, so even
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in gives us on odd number in our sequence.
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And now, when we're finding the median of an
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odd numbered sequence, we know that we take the
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total number which we normally call end. But in
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this time, I'll call it M. We take
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the total number, add one and divide by two
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. And that is our, uh, our sequence
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total. Right, So in. But in this
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instance, we have, um, how many terms
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we're gonna have. What would end is to we
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had three and when and was four. We had
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five. So when S O. M. Is
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gonna equal n plus one So if we have end
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in the median, Big M is going to be
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a X and plus one plus one over two,
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which is an over to plus one so X and
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over two plus one more second look like well,
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we know and over two of the whole number because
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it because it is because it is even. So
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, what's X and over to post one Will x
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one They're X one is one or another way of
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saying that is a 20 x two is a to
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the first. An X three is a to the
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second so we can see that X So X m
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is just a to the M minus one. That's
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a general rule. Now, if we have a
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feeling for X and over to plus one, we're
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looking for X n over two plus one. We
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know that that's gonna be a to the end over
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to plus one minus one, which is just equal
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to the median is gonna be He's gonna be equal
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to a o. R race the end over to
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And so that is what the media is gonna be
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. And I think that corresponds to answer C in
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this multiple choice question, Sylvester finally