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Now we're going to look at an example[br]problem using our calculator.

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This is the TI thirty X two S, [br]and this is the model I recommend.

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Other calculators will do the exact same functions,[br]but things happen in a little bit different order.

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And where the buttons are and what[br]they call them are a little bit different.

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So if you're not sure how to use your[br]calculator, play around with it.

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And if you still need help, then please[br]feel free to come see me.

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We're going to solve this problem, and we're [br]using numbers that are in scientific notation.

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And I want to show you how to enter[br]this correctly into your calculator.

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So my problem is six point one times ten to the fifth, [br]divided by one point two times ten to the minus third.

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So I have two issues I have to worry about: [br]one, how do I enter this number (the 6.1 x 10^5)

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in scientific notation into my calculator, [br]and how do I enter the denominator correctly

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so that the right calculation is done. [br]So, we're going to turn our calculator on.

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And I'm going to type 6.1, and then [br]I have the times 10 to the fifth.

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The way we do this on the [br]calculator is we use this EE function.

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So if I look here at this button that has [br]x to the -1, above it in purple it says EE

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and that means scientific [br]notation--the exponent.

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So I'm going to hit 2nd because I wanted [br]to use the purple function there.

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I press EE, so it shows an E on my screen.[br]And then I put a 5 in.

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Now note, I did not put a multiplication sign in, [br]I did not type 10, I just put 6.1 E to the fifth.

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And that means exactly the same as this: [br]6.1 times 10 to the fifth.

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Now I'm going to divide, then I'm [br]going to put in my denominator: 1.2.

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Again, I'm going to use my EE function, [br]so I do 2nd, EE.

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And this time my exponent is to the negative [br]three, so I use my minus sign here,

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this is the negative sign--excuse me, the negative[br]sign, not the subtraction sign--minus three.

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And when I hit equals, that will show me my answer. [br]And it's showing it here in scientific notation.

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So, I have 5.1--because I'm going to round it to [br]one decimal place--5.1 times ten to the eighth.

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So, we're going to write that down.

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Now, sometimes your calculator won't[br]be showing it in scientific notation,

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or you want to get something [br]out of scientific notation.

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And what you do is you[br]use the 2nd button again.

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And here where it has DRG which stands for degree, [br]above it you see SCI/ENG, so "scientific/engineering."

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So, I hit 2nd and scientific/engineering, and I want [br]to make sure SCI--that will put it in scientific mode.

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If I want to just see the number NOT in scientific [br]notation, I choose FLO for "Flo" [floating decimal]

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and that will show me the[br]number NOT in scientific notation.

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So here you don't see the times ten to the eighth, [br]you see the whole number written out.

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And I can go back to scientific notation, [br]and now again it shows it in scientific notation.

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So, that's the correct way to do the problem.[br]What I want to show you is how you DON'T

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want to do this, because I want you to see [br]that there is a difference in the answer.

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So, here we've used the EE function,[br]our scientific notation, to show these values.

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Let's look at what happens if instead of using[br]the EE button, I use "times ten to the fifth."

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Now for the numerator it [br]doesn't make a big deal.

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However, we're going to run into a[br]problem with our denominator.

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I'm going to hit divide, one point two, [br]times ten to the minus third.

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Now, when I hit the equals sign, [br]I get my answer, it's in scientific notation.

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But, note it's five point one times ten to the second,[br]a very different answer than what I saw before.

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And the reason for that is because what [br]really happened is the calculator took

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6.1 x 10^5 divided by 1.2 [br]and multiplied by 10^-3.

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And that's not what we wanted to happen,

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so you need to make sure you use scientific [br]notation so that you get the correct answer.