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fDesc[0] = "Math Center Level 1 consists of Graphing calculator 2D, Advanced Calculator, and Simple Calculator called from the Control Panel.<br /> <br /> Simple calculator is a general purpose calculator which combines use simplicity and calculation power. It handles simple arithmetic operations and complex formulas.<br /> <br /> The Simple Calculator has three windows or boxes: Edit Window, Result Window, and History Window. In the Edit Window you enter formulas using buttons and keyboard. When you use a keyboard, you can use all standard rules of text editing. The most convenient is use of numerical pad on the right of standard keyboard. Buttons also provides full functionality of Simple Calculator. If you mistake in typing formula, like square root of a negative number, you just get a message in the Result Window that the formula is unclear. The Simple Calculator tries to handle all possible ambiguities, following the standard mathematical rules. For example, formula 3/-4 - 5^2 will be treated as 3/(-4) - (5^2) . If you want to be completely sure in the result, use parentheses.<br /> <br /> Advanced Calculator is a step farther in complexity comparing to the Simple Calculator. The Advanced Calculator has two editing windows. One is for editing x, and the second is for editing f(x). In the x window you can enter any number or formula which contains numbers. In the f(x) window you can enter formulas containing numbers and formulas containing x. First, x will be calculated. Then the result for x will be substituted into the formula for f(x). The presence of two editing windows demands switching between windows. You can do it by clicking buttons &quot;go to x&quot; and &quot;go to f(x)&quot;, or by clicking inside the window. If you forget to enter x, then the x=1 will be assumed. If you forget to enter f(x), then f(x)=x will be assumed.";

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