MET 107 Getting Started in Mathcad Document Set 1. The majority of these documents are taken from the Mathcad Resources (Help) pages.

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1 The majority of these documents are taken from the Mathcad Resources (Help) pages. The Math Toolbar The Math toolbar, whose buttons bring up toolbars of math operators, is docked just under the main menu. You can also undock it and drag it around the screen. Choose Toolbars > Math from the View menu if you don't see it. If you let your mouse hover over each of the buttons on the bar in turn, you see a tooltip telling you what toolbar each button brings up. Calculator toolbar Graph toolbar Vector and Matrix toolbar Evaluation toolbar Boolean toolbar Programming toolbar Greek Symbol toolbar Symbolic Keyword toolbar Calculus toolbar Click on one of these buttons in the Math toolbar to bring up the associa operator toolbar. You can then use the operator toolbar to insert math symbols into your worksheet. Hover over any button for a tooltip giving brief description and keystrokes. Page 1 of 7

2 The Modifier button on the Symbolic toolbar opens up an additional toolbar of keywords. The Formatting Toolbar The Formatting toolbar helps you easily format your text and math. If the Formatting toolbar is not showing, select Toolbars > Formatting from the View menu. Finally, the status line at the bottom of the Mathcad window gives you status alerts, keyboard shortcuts, and other helpful information. It also lists the calculation status of your worksheet - "AUTO" means that the worksheet is in automatic mode, which means Mathcad automatically recalculates math expressions if you make changes to your worksheet. You can turn off Automatic Calculation from Calculate in the Tools menu. Page 2 of 7

3 Entering Math Expressions MET 107 Math in a Mathcad worksheet appears in familiar math notation - division with a fraction bar, exponents in a raised position, and built-up fractions just as you would see in a book. Here are some quick exercises to learn a few keystrokes and toolbar buttons. You will also learn how to get a numeric result and to modify its format. Definitions numeric expressions - expressions involving numbers and operators symbolic expressions - expressions involving numbers, unknowns (variables), and operators result format - type of result, including: decimal, fractional, scientific, etc. Entering a Numeric Expression 2+1/ Tip: Don't press the Spacebar between parts of the expression. Mathcad enters the correct spacing as you type. (9+3)/2* Entering a Symbolic Expression 3x+2y 3x + 2y Getting a Result Click: 2+1/2= = Tip: Notice that the result is in decimal format, the Mathcad default. Page 3 of 7

4 To set the number of decimal places etc. select Format Result. If You Make a Mistake Sometimes you may type the wrong number or letter. To fix your mistake, use the Undo and Redo arrow buttons or choose Undo from the Edit menu. Sample Math Expressions: Example 1 1/2 [Spacebar] When you are in an exponent and you want to continue entering more of the expression, you use the spacebar to move down from the exponent. Example 2 x^2 [Spacebar] +2x+1 x 2 + 2x + 1 Page 4 of 7

5 x+6[spacebar]*(x^3[spacebar]-1) ( ) ( x+ 6) x 3 1 The exponent operator in Mathcad is called a sticky operator because your keystrokes stick to the exponent position until you specifically move back to the baseline of the expression by pressing the spacebar. Other sticky operators include square roots, subscripts, and division. To Enter Text Tip: Notice that the blue editing lines change to a red The [Spacebar] The vertical editing line when you press the spacebar. That is when the region changed from a math region to a text region. "The quick brown fox The quick brown fox Tip: Another way to create a text region is to type a ["] in a blank spot in the worksheet. You can also select Text Region from the Insert menu. First Things First All worksheets are comprised of regions - text regions, math regions, graphs, and images. Math regions often depend on other math regions to calculate correctly. Here's an example: Define a variable: x := 3 Then use it, like this: Or, like this: x 2 = 9 y:= x 2 y = 9 Page 5 of 7

6 But, you cannot define a variable-dependent calculation: p + 2 = Tip: The red variable with no result indicates an error - if you click on it you see an error message. First define your variable: p := 14 A definition must appear above or to the left of where it is being used, a procedure referred to as top/down, left/right protocol. After re-ordering the expressions: p := 14 p + 2 = 4 Tip: If you enter one definition and press [Enter], your cursor is in the right position to enter another vertically aligned region below it. Tip: If you enter one definition and press [Tab], your cursor is in the right position to enter another horizontally aligned region next to it. Align regions horizontally by selecting them and clicking the button on the main toolbar. Align regions vertically by selecting them and clicking the button on the main toolbar. Page 6 of 7

7 Zero Threshold Similar to the threshold that the general display option uses to determine if a result is displayed in scientific or decimal notation, Mathcad uses an internal threshold to determine how small a result must be to display as zero. You can specify a threshold from 0 to 307 under Format / Result / Tolerance. (It is 15 by default.) When expressed in scientific notation, exponents strictly greater than the specified threshold will be displayed as 0. To have a display as 0, change the zero threshold setting to be at most 9. Note: This is a worksheet-wide setting and cannot be changed on a region-by-region basis. End of Document Page 7 of 7