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Greater than and less than symbols

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    Most of us are familiar with the equal
    sign from our earliest days of arithmetic.
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    You might see something like 1 plus 1 is
    equal to 2.
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    Now a lot of people might think when they
    see
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    something like this that somehow equal
    means give me the answer.
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    1 plus 1 is a problem, equal means give me
    the answer, and 1 plus 1 is two.
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    That's not what equal actually means.
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    Equal is actually just trying to compare
    two quantities.
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    When I write 1 plus 1 equals 2, that
    literally
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    means, that what I have on the left hand
    side
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    of the equal sign, is the exact same
    quantity as
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    what I have on right hand side of the
    equal sign.
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    I could have just as easily have written 2
    is equal to 1 plus 1.
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    These two things are equal.
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    I could have written 2 is equal to 2.
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    This is a completely true statement, these
    two things are equal.
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    I could have written 1 plus 1 is equal to
    1 plus 1.
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    I could have written 1 plus 1 minus 1 is
    equal to, is equal to 3 Minus 2.
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    These are both equal quantities.
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    What I have here on the left hand side,
    this is, this is 1, 1 plus 1 minus
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    1 is 1, and this right over here is 1,
    these are both equal quantities.
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    Now, I will introduce you to other ways of
    comparing numbers.
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    These are, the equal sign is when I have
    the exact same quantity on both sides.
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    Now we'll think about what we can do
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    when we have different quantities on both
    sides.
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    So let's say I have the number 3, and
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    I have the number 1, and I wanna compare
    them.
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    So clearly, 3 and 1 are not equal, in fact
    I
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    can make that statement with a not equal
    sign, so I
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    can say 3 does not equal 1, but let's say
    I
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    wanna figure out which one is larger and
    which one is smaller.
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    So, if I wanna have some symbol, where I
    can compare them, where
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    I can tell, where I can, I can state which
    of these is larger.
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    And the symbol for doing that is
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    the greater than symbol, the greater than
    symbol.
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    This literally would be read as 3 is
    greater than 1, 3 is a larger quantity.
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    And if you need, if you have trouble
    remembering what this, that this
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    means greater than, the larger quantity,
    the
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    larger quantities on the opening, the
    larger
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    on the, the, the larger, I guess if you
    could view this as some
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    type of an arrow or, I guess a shet, well,
    some type of symbol.
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    Then this is the bigger side.
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    Here you have this little teeny tiny
    point, and here you
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    have the big side so the larger quantity's
    on the big side.
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    This would literally be read as 3 is
    greater than, so let me write that down.
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    Greater than, 3 is greater than 1.
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    And once again, it just doesn't have to
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    be numbers like this, I could write an
    expression.
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    I could write, I could write 1 plus 1 plus
    1, is greater than,
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    is greater than, let's say, well just one
    1 right over there.
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    This is making a comparison.
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    But what if we had things the other way
    around?
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    What if I wanted to make a comparison
    between 5, and let's say 19.
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    So now the greater than symbol wouldn't
    apply,
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    it's not true that 5 is greater than 19.
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    I could say that 5 is not equal to 19,
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    so I could still make, I could still make
    this
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    statement, but what if I wanted to make a
    statement
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    about which one is larger and which one is
    smaller?
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    Well if in plain English, I would wanna
    say 5
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    is less than 19, so I would wanna say, let
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    me write that down, I wanna write 5 is
    less
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    than, 5 is, is less than is less than 19.
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    That's what I wanna say, and so we just
    have to think
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    of a mathematical notation for writing is,
    for writing is less than.
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    Well if this is greater than it makes
    complete
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    sense, and let's just swap it around,
    let's make, once
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    again, the point point towards the smaller
    quantity and the
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    big side of the symbol point to the larger
    quantity.
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    So here 5 is a smaller quantity, so I'll
    make the point point
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    there, and 19 is a larger quantity, so
    I'll make it open like this.
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    And so this would be read as 5 is less
    than 19, 5 is a smaller quantity than 19.
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    I could also write this as, I could write
    1 plus 1 is less that 1 plus 1 plus 1.
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    It's just saying that this statement, this
    quantity, 1
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    plus 1, is less than 1 plus 1 plus 1.
Title:
Greater than and less than symbols
Video Language:
English
Duration:
05:04

English subtitles

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