Scientific Notation on the TI 30 X IIS

now we're going to look at an example problem using our calculator this is the ti3x 2s and this is the model recommend other calculators will do the exact same functions but things happen in little bit different order and where the buttons are and what they call them are little bit different so if you're not sure how to use your calculator play around with it and if you still need help then please feel free to come see me so we're going to solve this problem and we're using numbers that are in scientific notation and want to show you how to enter this correctly into your calculator so my problem is 6.1 * 10 5th / 1.2 * 10us 3r so I've got two issues have to worry about one how do enter this number the 6.1 * 10 5th in scientific notation in my calculator and how do enter the denominator correctly so that the right calculation is done so we're going to turn our calculator on and I'm going to type 6.1 and then have the times 10 the 5th and the way we do this on the calculator is we use this function so if look here this button that has to Theus one above it in purple it says and that it means scientific notation the exponent and so I'm going to hit second because want it to use the the purple function there and press so it shows an on my screen and then put five in now note did not put multiplication sign in did not type 10 just put 6.1 to the 5 and that means exactly the same as this as 6.1 * 10 5th now I'm going to divide side then I'm going to put in my denominator 1.2 again I'm going to use my function so do second and this time my exponent is to the -3 so use my minus sign here this is the negative sign not or excuse me the negative sign not the subtraction sign minus 3 and when hit equals that will show me my answer and it's showing it here in scientific notation so have 5.1 because I'm going to round to to one decimal place 5.1 * 10 to 8 so we're going to write that down now sometimes your calculator won't be showing it in scientific notation or you want to get something out of scientific notation and what you do is you use the second button again and here where it has drg which stands for degree above it you see so scientific engineering so can hit second and scientific engineering and want to make sure that will put it in scientific mode if want to just see the number not in scientific notation choose Flo for flow and that will show me the number not in scientific notation so here you don't see the times 10 to the eth you see the whole number written out and can go back to scientific notation and now again it shows it in scientific notation so that's the correct way to do the problem what want to show you is how you don't want to do this because want you to see that there is difference in the answer so here we've used the function our scientific notation to show these values let's look at what happens if instead of using the button use times 10 to the 5th now for the numerator it doesn't make big deal however we're going to run into problem with our denominator I'm going to hit divide 1.2 * 10 to the -3 now when hit the equal sign get my answer it's in scientific notation but note it's 5.1 * 10 the 2 very different answer than what saw before and the reason for that is because what really happened was the calculator took 6.1 * 10 5 divided by 1.2 and multiplied by 10 Theus 3r and that's not what we wanted to happen so you need to make sure you use scientific not ation so that you get the correct answer