Microsoft Office Tutorials and References

In Depth Information

Plotting functions with two variables

The preceding section describes how to plot functions that use a single variable (
x
). You also can plot functions

that use two variables. For example, the following function calculates a value of
z
for various values of two

variables (
x
and
y
):

z = SIN(x)*COS(y)

Figure 17-16 shows a surface chart that plots the value of
z
for 21
x
values ranging from 2 to 5 (in 0.15 incre-

ments) and for 21
y
values ranging from –3 to 0 (also in 0.15 increments).

Figure 17-16:
Using a surface chart to plot a function with two variables.

Figure 17-17 shows a general-purpose, two-variable plotting application, similar to the single-variable work-

book described in the previous section. The data for the chart is a 25 x 25 data table in range M7:AL32 (not

shown in the figure). To use this application

1.
Enter a formula in cell B3. The formula should contain at least one
x
variable and at least one
y
variable.

In the figure, the formula in cell B3 is

=SIN(x)*COS(y*x)