Mike's Toolbox Scientific Calculator
is similar to actual calculators you might buy in the store. It has a numeric keypad
for entering numbers, and the other buttons operate on the numbers that have been
entered. This page will show you what each button does so that you can use the
calculator most effectively.
Here is a full working calculator with the different sections highlighted in different
colors. Use the colors to find the explanations below.
Numeric Entry
...
Numbers: these buttons are used to enter numbers into the calculator
Decimal Point: inserts a decimal point at the end of the number being entered
Change Sign: changes the sign of a number from positive to negative or vice versa —
has no effect if the number displayed is equal to zero
Clear: clears the display and cancels any pending operation such as if you were in the
middle of calculating the sum of two numbers; has no effect on the memory functions (see below)
Clear Entry: clears the display but remembers any current calculation being performed —
use this button if you make a mistake entering a number and want to re-enter it
Delete: erases the last digit of the displayed number
Help: displays this help page
Arithmetic Functions
Addition: enter a number, press +, then enter a second number and press = to calculate the
sum of the two numbers
Subtraction: enter a number, press −, then enter a second number and press = to
calculate the difference between the two numbers
Multiplication: enter a number, press ×, then enter a second number and press =
to calculate the product of the two numbers
Division: enter a number, press ÷, then enter a second number and press =
to calculate the first number divided by the second
Calculate: performs the current calculation as described above
Basic Operations
Square: computes the square of the displayed number; for example if the display shows
the number 4, the calculator will replace that with 16, which is 4 × 4
Cube: computes the cube of the displayed number; for example if the display shows
the number 4, the calculator will replace that with 64, which is
4 × 4 × 4
Exponentiation: enter a number y, then press the y^{x} button followed by the
number x and press = to compute y to the x power
Square Root: computes the square root of the displayed number; for example if the
display shows the number 16, the calculator will replace that by the number 4 since
4 × 4 is 16. This is the opposite of the x^{2} button.
Cube Root: computes the cube root of the displayed number; for example if the
display shows the number 8, the calculator will replace that by the number 2 since
2 × 2 × 2 is 8. This is the opposite of the
x^{3} button.
Factorial: computes the factorial of the displayed number; for example if the display
shows the number 4, the calculator will replace that by the number 24 since
4! = 4 × 3 × 2 × 1 which is 24
Swap: swaps the stored number with the displayed number prior to performing a calculation;
for example if you first enter the exponent x, then press the y^{x} button followed
by the number y, you can fix your mistake by pressing x↔y prior to pressing the
= button.
Inverse: calculates the reciprocal of the displayed number, which is 1 divided by the
number; if you multiply a number by its inverse, the result is 1
Round: rounds the displayed number to the nearest whole number
Percentage: if no operation is pending, then the displayed number is divided by
100; otherwise what happens depends on the current calculation as follows:
Percentage Addition: to calculate a 20 percent increase of the number 5, for example,
first enter the number 5, then press + followed by the number 20 and
the % button; at that point the calculator will replace the displayed
value of 20 with 20 percent of 5, which is 1 — the
calculator remembers the number 5 and the fact that addition is being
performed, so when you finally press the = button, it adds
5 + 1 and displays the result of 6
Percentage Subtraction: to calculate a 25 percent decrease of the number 8, for example,
first enter the number 8, then press − followed by the number 25
and the % button; at that point the calculator will replace the displayed
value of 25 with 25 percent of 8, which is 2 — the
calculator remembers the number 8 and the fact that subtraction is being
performed, so when you finally press the = button, it subtracts
8 − 2 and displays the result of 6
Percentage Multiplication: calculates simple percentages; to find 15 percent
of your $60 restaurant tab, enter 60 followed by × then 15 and
the % button — the result of $9 is displayed
Percentage Division: this is an odd one; if you want to know how many years
it will take to double your money if it earns, say, 6 percent per year,
then you would enter 2, since that is the multiple of your investment, then
the ÷ button followed by 6 and the % button
Memory
If you calculate an important result and want the calculator to remember it for use later,
you will want to use the memory functions shown here:
Memory Store: stores the displayed number in the calculator's memory, erasing any
previously stored number
Memory Plus: adds the displayed number to the number in the calculator's memory and
stores the result in the memory; also increases an internal counter used by the AVG
button
Memory Minus: subtracts the displayed number from the number in the calculator's memory
and stores the result in the memory; also increases an internal counter used by the AVG
button
Memory Recall: displays the number currently stored in the calculator's memory
Memory Clear: stores the number zero in the calculator's memory and resets the counter
used by the AVG button to zero as well
Average: computes the average of all the numbers added to the memory using the
M+ and M− buttons
Trigonometric Functions
Pi: displays the famous constant representing the ratio of the circumference of a
circle to its diameter; approximately 3.1415926
Sine: computes the sine of the displayed number expressed in radians
Arcsine: computes the number of radians of the arc whose sine is the displayed
number (which must be between −1 and 1)
Cosine: computes the cosine of the displayed number expressed in radians
Arccosine: computes the number of radians of the arc whose cosine is the displayed
number (which must be between −1 and 1)
Tangent: computes the tangent of the displayed number expressed in radians
Arctangent: computes the number of radians of the arc whose tangent is the displayed
number
Logarithms
Euler's Number: displays the value of the important constant which is the base
of the natural logarithm; approximately 2.71828
Base-10 Logarithm: computes the exponent of the number 10 required to calculate the
displayed number
Base-2 Logarithm: computes the exponent of the number 2 required to calculate the
displayed number
Natural Logarithm: computes the exponent of the number e required to calculate the
displayed number
Exponentiation Base-10: computes the power of 10 where 10 is raised to the displayed
number; for example, if 2 is displayed, it will be replaced by 100 which is 10^{2}
Exponentiation Base-2: computes the power of 2 where 2 is raised to the displayed
number; for example, if 5 is displayed, it will be replaced by 32 which is 2^{5}
Exponentiation Base-e: computes the power of e where e is raised to the displayed
number