WEBVTT

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- In this video we are
going to take a look at

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finding the absolute value

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on the TI-83 Plus and TI-84
series of calculators.

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Fairly simple, so we are just

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going to concentrate on the
home screen for right now.

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If you have to find the
absolute value of say,

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X when the absolute value
of X is equal to seven,

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that's going to take some graphing.

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And so if you are not there
yet, don't worry about it.

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I'll have that in a different video.

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Alright, let's go ahead and get started.

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So, I've got my calculator here

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and I just want to find the absolute value

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of negative three.

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You might know that right
off the top of your head

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that the absolute value of negative three

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is in fact three because,

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the absolute value stands
for the distance between

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the number inside and zero.

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And you take three steps
in order to get to three

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from zero from negative three.

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But, if you want to do
it in the calculator,

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just because,

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then you could do so

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using the math button.

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Press math.

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It opens up a set of menus

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and you scroll over to num,
which stands for number

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and this is where all
of the stuff you might

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want to use on numbers would go.

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And the very first one, abs
stands for absolute value.

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So we are going to press
enter to activate that

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and we are just going to
put in negative three.

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Now don't forget, negative is down here

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right next to the enter button,

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not one of the blue
buttons, so negative three.

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Close the parenthesis, always a good idea

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even though it might always be necessary.

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Press enter, and we get
the answer of three.

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And so you can use this to check yourself

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if you're really not sure.

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Should I change the sign or should I not?

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A very common mistake that I've seen

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in students in the past is simply that

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when they get this idea that
it's just switch the sign

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and it's not just switch the sign

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as we'll see in this next one.

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So in this next example,

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we want to take the
absolute value of eight.

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And so we ask ourselves,
well how far away is eight

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from zero?

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Well,

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well, it could be eight but
do I switch the sign or not?

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Well, let's check.

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So we press the math button,

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that gets us over here to
our little set of menus.

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We scroll over to num, for number,

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and we press enter for absolute value

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or you could press the number one

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and it will enter absolute
value directly on the screen.

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Let me put an eight,
close the parenthesis,

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and hit enter.

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And we get eight.

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And so our answer is eight,
so we don't switch the sign.

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Oh, that's a good idea.

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Alright, that's how
you find absolute value

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on your TI-83 Plus or TI-84
series of calculators.