Module 2
Tips for using the calculator to solve formulas.
The type of calculator needed for this class has many different functions on it. The easiest
to pick out is probably the “log” function. This function will be covered in Module 8.
You will start to practice using your calculator here in Module 2.
There are two basic styles of calculator.
There is the calculator that processes each operation/function as it is punched into the
calculator. I will call this a common calculator. This calculator only shows the numbers
you put into the machine. None of the operations or functions will appear.
There is also the calculator that displays the operation/function as it is punched into the
calculator. I will call this a display calculator. The display calculator has room on the
screen to display every number, operation, function and symbol you punch into the
machine and it returns an answer when you hit enter or “=”. A graphing calculator like
the TI-83 is a display calculator.
The order of operations is very different between the two styles and it is very important
that you learn how to use your calculator.
Here are some examples of how to use some of the functions of your calculator on the
formulas in the Practice Problems from Module 2.
Pythagorean Theorem
c  a2  b2
This formula would be used to find the length of the longest side of a right triangle.
You have to square the values given for a and b, add those values together and then take
the square root of the sum. These operations can be found on your by looking for the
following symbols on or above the buttons.
Look for the following symbols on your calculator:
x2 is the button to push if you want to square a number.
or
x is the button to push if you want to take the square root of a number.
The following is but one way you can enter these numbers and operations into your
calculators to use the formula given above. I am using a = 3.5 and b = 4.75 in this
example.
Operations on a Common Calculator
Operations on a Display Calculator
1) Enter 3.5 into the calculator.
1) Enter 3.5 into the calculator.
2) Hit the x2 button. The display
2) Hit the x2 button and the display
should read 12.25 now. If it doesn’t,
will read “3.52”.
hit the “=” button.
3) Record 12.25 on a piece of paper.
4) Enter 4.75 into the calculator and
repeat step 2. You should record
22.5625 this time.
5) Add 12.25 and 22.5625 on the
calculator. Your display should read
34.8125.
6) Hit the
button and your display
should read 5.900211861
something very close to this. You
shouldn’t have to hit the “=” button
to take the square root of a number.
3) Hit “enter” and 12.25 will appear
on your display.
4) Hit “+” and repeat steps 1 & 2
using 4.75 and the display will read:
Ans + 4.752
5) Hit “enter” and the display will read
34.8125. Record this value on
paper.
6) Hit the x button and enter
34.8125. Hit the enter button and
5.900211861 or something very
close should appear in the display.
Thus, c = 5.900211861 when a = 3.5 and b = 4.75.
Cobb-Douglas Production Formula
q  cK a Lb
This formula can be used to predict production costs and profits.
The exponents, a and b, are usually very small numbers like .03 and .45. We haven’t
discussed the implications of this yet but we can still practice using these functions on a
calculator.
I will use the following values in my example:
c = 2.25, K = 331, L = 2500, a = .03, b = .45
Operations on a Common Calculator
Operations on a Display Calculator
The button you need to find on your
The button you need to find on your
calculator has one of these symbols on it:
calculator has this symbol on it: “^”
y
x
x or y .
1) Enter 331.
1) Enter 2.25 and the multiplication
y
2) Hit the x button and enter .03.
button. The display will use either
3) Hit the “=” button and the display
* or x to indicate multiplication.
should read 1.190131198.Record
2) Enter 331. Hit the ^ button and
this value on a piece of paper.
enter .03. The display should read:
4) Enter 2500 and repeat steps 2 and 3
2.25*331^.03
using .45 for the second number.
3) Hit enter and the display will show
You should record 33.81216689.
2.677795195.
5) Multiply 2.25, 1.190131198 and
4) Hit the multiplication button and
33.81216689 to get a value for q.
the display will show “Ans *”.
5) Enter 2500 ^.45
6) Hit the enter button get the answer
for q.
Thus, q = 90.54205803 when c = 2.25, K = 331, L = 2500, a = .03, b = .45.