II. Menu Keys - Keys that offer choices

B. MODE

For most of the calculations you perform, you will use the MODE window shown in the figure below.

To change the mode, move the cursor over the selection you want and then press . To return to the home screen, press .

1. Normal Sci Eng

For most of your calculations you will leave the mode in Normal. This expresses the number with digits to both the left and right of the decimal point. If the number is too large to be shown in normal mode, the calculator will automatically switch to scientific notation.

Sci (scientific) and Eng (engineering) notation will express the answer as a power of 10. Scientific will have only one digit left of the decimal, but engineering may have up to three digits left of the decimal with the exponent being a multiple of 3.

Example: Express the number 123,456,789.001 in each mode. In the screen, the numbers are in the order: normal, scientific, and engineering.

2. Float 0123456789

This will set the number of digits to be displayed.

Float will display up to 10 digits, plus the sign and the decimal. If you select one of the other numbers, that number will be the number of digits that will be shown to the right of the decimal for all calculations. Unless there is some particular reason for doing otherwise, you should leave the setting on float.

3. Radian Degree

These are mode settings used in trigonometry and when using trig functions in calculus. These settings only affect calculations or graphs involving trigonometric functions. They will have no effect on other calculations or graphs.

It is essential that you have the correct mode because the results will be very different in each mode. If you try to graph a trig function with the degree mode selected but the graph window set with radian measurements, you will get a result much like that shown below. However, if you use ZTrig, it will automatically set the window to the selected mode.

Example: Graph the function y=sin x with the mode set in degree but the window set to [Xmin,Xmax]=. Then use ZTrig to get the correct graph.

Change the mode.	Enter the function.	Set the window.
Incorrect graph.	Use ZTrig.	Correct graph.

4. RectC PolarC (rectangular coordinates and polar coordinates)

This determines the type of coordinates that will be displayed when TRACE is used. RectGC stands for rectangular graphing coordinates and gives the coordinates in (X,Y) form. PolarGC stands for polar graphing coordinates and will give the coordinates in polar form. PolarGC is usually used when you are graphing in polar mode.

RectGC On Function Mode	PolarGC On Polar Mode

5. Func Pol Param DifEq

These are graphing modes.

Func (function) mode is the mode you will use most often. It is the mode for any function that is to be graphed with rectangular coordinates (y is a function of x). (See the figure above in 4.)

Pol (polar) mode plots functions that are polar form. The function r is a function of . You will use this mode is some algebra applications, but you will primarily use this mode in calculus. To use the TRACE in this mode you should change to polar graphing coordinates. (See the figure above in 4.)

Par (parametric) mode defines both x and y as a function of the variable t.

Put in parametric mode.
Press and .
Enter the functions.
Use ZDECM.

DifEq (differential equation graphing) plots differential equations in terms of the variable t.

6. Dec Bin Oct Hex (decimal, binary, octal, hexadecimal)

These are the number base modes. The setting displays the numbers in the indicated base. In algebra, trigonometry, and calculus, you will use only the decimal setting.

7. RectV  CylV  SphereV (rectangular, cylindrical, spherical)

These are the vector coordinate modes. You will only use the rectangular mode until you reach a higher level calculus course.

8. dxDer1  dxNDer (exact differentiation, numeric differentiation)

These modes are used in the numerical calculation of a derivative. dxDer1 is more accurate than dxNDer, but it is more restrictive of the types of functions that can be used.