Microsoft Excel

Excel offers many more options than you would find on a calculator or paper & pencil. Consider this question: Why would you drive a car or fly in an airplane when you could walk or take a boat? If you only need to visit your friend next door, you most likely would walk (not take an airplane). If you just want to add three numbers to find the sum, you probably would use a calculator or paper & pencil.

The choice of tool to use is yours, but consider that two primary reasons for using Excel relate to speed and capability (the same as your choice of transport from one location to another).

EXAMPLES OF SPEED (possible to use calculator, but Excel is better option):

• You have a column of 123 numbers in MS Word. You want to find the SUM of these numbers. You highlight the column of numbers in Word and paste them into Excel (assume you pasted in column B, rows 1-123). You then go to the first blank cell at the bottom of the list of numbers (cell B124) and enter =SUM(B1:B123).
• You have two dates (3/14/2008 and 1/21/2010) and want to find the number of days between the dates. Enter your first date in cell A1 and your second date in cell B1. In cell C1 enter =B1-A1. Another option would be to use a single entry of ="1/21/2010" - "3/14/2008"
• Find the SUM of twenty columns of numbers, then find the average (MEAN) value of the totals.

EXAMPLES OF CAPABILITY (probably could not use calculator):

• Link to data from an external source and draw a graph in real time.
• Save twenty columns of numbers, so you can make changes to three of the numbers in the entire list and automatically update the relevant totals.
• Automatically extract stock prices from an online database and track prices over time. Highlight each cell where the price was above or below a target price.

In Excel, the ACos function returns the arccosine (in radians) of a number.

The syntax for the ACos function is:

ACos( number )

number is a number between -1 and 1. It is the cosine of the angle that you wish to find.

Applies To:

• Excel 2007, Excel 2003, Excel XP, Excel 2000

x and R chart

x and s chart

ImR chart

XmR chart

Three-way chart

p-chart

np-chart

c-chart

u-chart

EWMA chart

CUSUM chart

Time series model

Regression Control chart

There are several stages to the calculation. These can be summarized in the formula

=10^(LOG(x)/3)

Where x = the number you want to find the cube root of. Excel example:

In cell A1 enter the number you want to find the cube root of. e.g. 125

In cell B1 enter the formula '=10^(LOG(A1)/3)' [omitting the 'quote' marks]

The formula will return the answer 5, which is the cube root of 125. [5x5x5=125] Explanation of formula: * LOG (x) converts the original number to a logarithm. * /3 divides the Log by three * 10^ raises 10 to the power of the result of the previous calculations The equals ('=') sign is required when writing formulas into cells in Excel.

Unfortunately there is no short way to find the cube root in excel, but the square root can be found by using =SQRT(number) An infinite number of 'roots' can be found by using =10^(LOG(x)/3). Just change the '3' to a number of your choice.

There are two ways to express exponents in Excel.

• =6^3
• =POWER(6,3)

Excel and also OpenOffice Calc have functions to do certain operations on complex numbers. The IMPOWER() function will handle what you want to do. Example: type the following in a cell =IMPOWER("-415+234i",1/3) and the result will be 5 + 6i. If you are using OpenOffice, then a semicolon is used rather than a comma in functions {=IMPOWER("-415+234i";1/3)}

The complex number is formatted as text. There are other functions: IMABS, IMARGUMENT, IMPRODUCT, etc. You can do a help search for Complex Numbers, or one of these functions that I mentioned.

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