### Scientific Notation on the TI-83

The TI-83 uses "Scientific Notation" for numbers in several different situations. This page illustrates such uses.

 Figure 1 Figure 1 shows the typical MODE settings. On the TI-83 press the key to move to this screen. The top line of the screen lets us know that the calculator is in mode. In this mode the calculator will display most of our usual values in the normal way. However, for extremely large numbers and for numbers relatively close to zero, the calculator automatically displays values in its "scientific notation". We will look at some such values in the next screen images. Also note that this calculator has been set to the Float mode. That is, the calculator will display up to 10 digits for a value but it will drop off any trailing 0's to the right of the decimal point. Figure 2 The TI-83 has been designed to display up to ten digits in numbers. Thus, in Figure 2, if we enter a ten digit number, such as 9865327418 the calculator displays that value in the normal way. However, if we enter an eleventh digit number, such as 98653274184, the calculator uses its "scientific notation", showing its limit of ten significant digits. In Figure 2 that value is displayed as which is the calculator's notation for our scientific notation, namely, 9.865327418 x 1010 In particular, note the calculator's use of the small, but upper-case, E to represent "times 10 raised to the power". Figure 3 Figure 3 gives a demonstation of the calculator's use of scientific notation for numbers close to zero. In particular, the calculator will display numbers that are greater than or equal to 0.001 (or less than –0.001) in their usual form. Thus, the first value in Figure 3, 0.0028975, displays in the normal fashion. However, the number 0.0002897 is between 0.001 and 0. For such a number, the calculator displays the value in scientific notation, as Note that the 12 digit number, .00289752784 is displayed rounded off to 10 digits. Figure 4 The earlier images illustrate how the calculator uses its scientific notation to display certain values. The calculator also allows us to enter values in scientific notation. In particular, we can enter the value 2.5*104 by pressing the keys which produces, on the screen, the characters Naturally, when we press the key, the TI-83 evaluates this as 25000 which it displays in the normal fashion. In the same way, the expression 2.5*10–2 is entered as which produces on the left side of the screen, but which evaluates to .025 and displays as such on the right side. On the other hand, evaluates to 0.0000025, but this is in the range of values that the calculator automatically displays in scientific notation. Therefore, that last entry in Figure 4 displays in scientific notation. Figure 5 Figure 5 continues with the idea of entering values in scientific notation, and having the calculator display the values in scientific notation, this time because they are more than 10 digits long. Also, the last entry in Figure 5 demonstrates how we might enter a value in scientific notation without the use of the keys, namely, by just typing it the way we say it. Figure 6 All of the work above assumes that the calculator mode setting was at . In Figure 6, we see that the calculator MODE setting has been changed to or SCIENTIFIC mode. Now, all values will be displayed in the calculator's scientific notation, no matter their size or how they were entered. Figure 7 Figure 7 illustrates the calculator output in scientific notation mode.