Example 1: Using the variable e instead of the exponential constant e
Maple allows you to use letters as variables even when that letter is also used to represent a particular mathematical object, such as the exponential constant e or the imaginary unit i. If you simply type e or i, you get the variable. In this example, the variable e has been used.
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Maple cannot plot just like it cannot plot when a does not have a value.
Solution 1 (Standard math notation): To plot this expression, replace with , where e is the exponential constant. (Note: When using standard mathematical notation in Maple, variables are displayed in italics, so e is the variable, and e is the constant.) You can enter the exponential constant by using the Expression or Common Symbols palettes, or you can enter it using symbol completion: Type 'e', then press the Esc key, and select Exponential 'e' from the menu.
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Solution 2 (Maple syntax): Use the exp() function to enter exponentials.
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plot(exp(x), x = 0..1);

Example 2: Using pi instead of Pi or
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plot(sin(pi*x), x = 1 .. 2);

Solution 1 (Maple syntax): When using Maple syntax, use "Pi" instead of "pi".
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plot(sin(Pi*x), x = 1 .. 2);

Solution 2 (Standard math notation): When using standard math notation, you can enter using symbol completion (type 'pi' and press Esc then select from the menu) or using the Common Symbols palette.
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Example 3: Using the variable i instead of the imaginary unit i
Maple allows you to use letters as variables even when that letter is also used to represent a particular mathematical object, such as the exponential constant e or the imaginary unit i. If you simply type e or i, you get the variable. In this example, the variable i has been used.
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Solution 1 (Standard math notation): To plot this expression, replace the variable i with the imaginary unit i. (Note: When using standard mathematical notation in Maple, variables are displayed in italics, so i is the variable, but i is the imaginary unit.) You can enter the imaginary unit by using the Common Symbols palettes, or you can enter it using symbol completion: Type 'i', then press the Esc key, and select Imaginary 'i' from the menu.
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Solution 2 (Maple syntax): Use uppercase "I" instead of lowercase "i". Maple uses I to represent one of the square roots of 1.
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Example 4: Variable mismatch: Parametric plot
In this example, the variable names used as arguments for the real functions to be plotted do not match the variable name given to the range variable.
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Solution: Changing one of the variable names to match the other solves this problem. Here, has been changed to
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Example 5: Forgetting to assign a value to a variable
The constant has not been assigned a value.
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Solution: Assign a value to
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Example 6: Forgetting to assign a value to a variable, multiple curves
Similar to Example 5, in the list of expressions to be plotted, the first expression, contains an undefined constant, b. As a result, only one curve is plotted.
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Solution: Assign a value to
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Example 7: Mismatched variables names: 3D plot example
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Solution:
The expression is defined in terms of z and y, but the ranges are defined in terms of x . Making them match fixes the problem.
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