I don't have the manual for the TI-84. I need to know how to use scientific notation on it.

Press Mode, and change display mode to float.

Exactly as you would any two numbers. If you are not comfortable with the notation enclose each number in scientific notation between parentheses. This way you can be sure that the priority of operations is respected.

The E is an engineering notation for 'x10^' so the answer there 4E-7 = 4 x 10^ -7 (I'm using the x as multiplication). I'm afraid there isn't a way of changing it (that I know of) but it is not difficult to learn, it's just a simple way of writing scientific notation!

If the absolute value is less than 0.001 then the TI-84 automatically switches to scientific notation. This is just the way the calculator works.

Sorry if that wasn't the answer you wanted to see, but there it is.

Press 2nd [SCI] to switch the calculator to display all results in scientific notation. The results are the same whether you do it in scientific notation or not, it's just how the number is displayed.

You're in Scientific or Engineering notation.

Press the MODE button to enter the mode editor. Highlight "NORMAL" on the first line and press ENTER. Highlight "FLOAT" on the second line and press ENTER. Press 2ND QUIT to exit the mode editor.

Hello,
It is quite simple. Press [MODE]. Right Arrow to select [SCI][ENTER]. You can then press [2nd][QUIT] to go to the HOME screen (normal screen).
However the number of digits displayed in the decimal part may still be set by the FLOAT option. You might want to select the number of significant digits by limiting the number of decimal digits in the FLOAT option
Hope it helps.

E is the calculators form of scientific notation. so 2.145274703E14
is really 2.145274703 x 10^14 or 214527470300000

I am just going to be frank here, you have to do the math. Move the decimal over a couple spaces and you will be fine. You can post back if you need to know how to convert it. Th ti-84 can't do everything. You need the ti 89 to do more advance things, which I don't think you need.

Hello,
If number format in MODE is set to Normal, and if the (absolute value of) the number is smaller than 0.001,the calculator displays it in scientific notation( with the E). By the way E( ) stands for x10^( ).