Finding Absolute Value on TI-83plus/TI-84 Calculators

Use the TI-83plus/TI-84 family of calculators to find the absolute value of a number. This same command can be used in the graphing screen as well.

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

finding the absolute value

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

Fairly simple, so we are just

going to concentrate on the
home screen for right now.

If you have to find the
absolute value of say,

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

that's going to take some graphing.

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

I'll have that in a different video.

Alright, let's go ahead and get started.

So, I've got my calculator here

and I just want to find the absolute value

of negative three.

You might know that right
off the top of your head

that the absolute value of negative three

is in fact three because,

the absolute value stands
for the distance between

the number inside and zero.

And you take three steps
in order to get to three

from zero from negative three.

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

just because,

then you could do so

using the math button.

Press math.

It opens up a set of menus

and you scroll over to num,
which stands for number

and this is where all
of the stuff you might

want to use on numbers would go.

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

So we are going to press
enter to activate that

and we are just going to
put in negative three.

Now don't forget, negative is down here

right next to the enter button,

not one of the blue
buttons, so negative three.

Close the parenthesis, always a good idea

even though it might always be necessary.

Press enter, and we get
the answer of three.

And so you can use this to check yourself

if you're really not sure.

Should I change the sign or should I not?

A very common mistake that I've seen

in students in the past is simply that

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

and it's not just switch the sign

as we'll see in this next one.

So in this next example,

we want to take the
absolute value of eight.

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

from zero?

Well,

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

Well, let's check.

So we press the math button,

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

We scroll over to num, for number,

and we press enter for absolute value

or you could press the number one

and it will enter absolute
value directly on the screen.

Let me put an eight,
close the parenthesis,

and hit enter.

And we get eight.

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

Oh, that's a good idea.

Alright, that's how
you find absolute value

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