The Greatest Integer Function; The Root Operation - Texas Instruments TI-83 Manual

The Greatest Integer Function

Find the greatest integer function, called the int func-
tion on the TI-82. Use this function to write C(x) in
the Warm-Up Exercise 4 of Section 1.1 in the text.
int(x) is the greatest integer less than or equal to x.
Thus, int(5.03) = 5 and int(7.8) = 7. So C(x) =
0.07int(x) + 0.10. This is easier to graph than using
the more complicated piecewise input.
Solution. Obtain the int function by first pressing the
MATH key. Now select the NUM menu by pressing
the £ key.
Now select the int function by pressing the key 4 .
Section 1.2 in Text

• The root Operation

• The intersect Operation
The root Operation
Find where the function y1 = 0.95x
Refer to Example 2 and Exploration 1 in the text.
Solution. First graph y1 using a screen with dimen-
sions [0, 400000] by [ 300000, 100000]. Now press the
keys 2nd CALC and you see the following.
Now press the key 2 and you obtain the following.
You are asked for a Lower bound. This means place the
cursor to the left of the zero. Press the key ENTER
and obtain the following.
38
300, 000 is zero.