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Comparing exponent expressions

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    - [Instructor] So we are asked to order
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    the expressions from least to greatest
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    and this is from the
    exercises on Khan Academy
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    and if we're doing it on Kahn Academy,
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    we would drag these little tiles around
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    from least to greatest, least on the left,
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    greatest on the right.
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    I can't drag it around 'cause this
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    is just a picture, so
    I'm gonna evaluate each
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    of these, and then I'm gonna rewrite them
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    from least to greatest.
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    So let's start with two to the third minus
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    two to the first.
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    What is that going to be?
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    Two to the third minus two to the first.
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    And if you feel really confident,
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    just pause this video and try
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    to figure out the whole thing.
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    Order them from least to greatest.
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    Well two to the third, that
    is two times two times two,
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    and then two to the first,
    well that's just two.
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    So two times two is
    four, times two is eight,
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    minus two, this is going
    to be equal to six.
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    So this expression right over here could
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    be evaluated as being equal to six.
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    Now, what about this right over here?
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    What is this equal to?
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    Well let's see, we have two squared
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    plus three to the zero.
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    Two squared is two times two and anything
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    to the zero power is
    going to be equal to one.
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    It's an interesting thing to think
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    about what zero to the zeroth power should
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    be but that'll be a
    topic for another video.
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    But here we have three
    to the zeroth power,
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    which is clearly equal to one.
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    And so we have two times two plus one.
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    This is four plus one,
    which is equal to five.
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    So the second tile is equal to five.
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    And then three squared,
    well three squared,
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    that's just three times three.
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    Three times three is equal to nine.
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    So if I were to order them from least
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    to greatest, the smallest of these
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    is two squared plus three
    to the zeroth power.
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    That one is equal to five,
    so I'd put that on the left.
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    Then we have this thing that's equal
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    to six, two to the third power
    minus two to the first power.
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    And then the largest value
    here is three squared.
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    So we would put that tile, three squared.
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    We will put that tile on
    the right, and we're done.
Title:
Comparing exponent expressions
Description:

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Video Language:
English
Team:
Khan Academy
Duration:
02:09

English subtitles

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