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How Do I

 Enter a Function?

Mathematical functions are represented in Maple as operators. There are various methods for entering a function: by using a template from the Expression palette, by using Maple's operator syntax directly, or by converting an existing expression into an operator.

Before you proceed, be sure to familiarize yourself with entering simple mathematical expressions. Open a new worksheet in Document mode, and ensure that you are in Math mode.

Using a Template from the Expression Palette

Follow the steps below to enter the operator $x\to {x}^{2}-1$ and assign it to a variable whose name is $f$.

 Step Description Illustration 1 Select the ${f}:={a}\to {y}$ template from the Expression palette. The green placeholder ${f}$ is selected automatically. 2 Type $f$, overwriting the green ${f}$. 3 Move the cursor among placeholders by pressing Tab. The ${a}$ is selected as you do so. Type $x$. 4 Press Tab to select the final placeholder ${y}$. To type ${x}^{2}$, first type $x$. Press Shift + ^ to bring the cursor into the exponent position and type $2$. 5 To bring the cursor back onto the base line, press the right arrow (→) key on your keyboard. 6 Type -. There is no need to type a space, as Maple automatically adjusts spacing for you. Type $1$. 7 Press Enter to execute the statement. Maple displays and labels the result of an executed statement on a new line. (For more information, see the How do I topic on evaluating expressions.) 8 To see what $f$ does, enter $f\left(1\right)$ and press Ctrl + = to evaluate it in-line. As you can see, Maple evaluates the expression ${x}^{2}-1$ at $x=1$, which yields ${1}^{2}-1=0$.

When Working with Templates From the Palettes, Keep These Tips in Mind:

 • If you accidentally move the cursor outside a template, simply move the cursor back into the template and press Tab to move to the next placeholder.
 • Use Shift + Tab to move back to the previous placeholder, if you have not overwritten it yet.

Using Maple's Operator Syntax

Follow the steps below to enter $x\to {x}^{2}-1$ and assign it to a variable whose name is $f$.

 Step Description Illustration 1 Type $f$, followed by a colon (:) and an equal sign (=). The colon-equals notation assigns the content on the right-hand side to a variable name on the left-hand side. 2 Type $x$. This is the name of the independent variable. To type the arrow, first type a minus sign -, then the right angle bracket (>). Maple automatically converts these characters to an arrow.   Tip: "->" looks like a right arrow. 3 Type ${x}^{2}-1$. For detailed instructions, see steps 4 to 6 of the example shown earlier. 4 Press Enter to execute the statement. Maple displays and labels the result of an executed statement in a new line. (For more information, see the How do I topic on evaluating expressions.) 5 To see what $f$ does, enter $f\left(1\right)$ and press Ctrl + = to evaluate it in-line. As you can see, Maple evaluates the expression ${x}^{2}-1$ at $x=1$, which yields ${1}^{2}-1=0$.

Converting an Existing Expression into an Operator

Suppose the expression ${x}^{2}-1$ has already been typed. Follow the steps below to convert it to the operator $x\to {x}^{2}-1$ and assign the result to a variable whose name is $f$.

 Step Description Illustration 1 Right-click any part of the expression (within the dotted outline). A context-sensitive menu is displayed. For more information, see the Context-Sensitive Menus subsection of the How Do I help page. 2 Select Conversions > Operator > $\mathbit{x}$. Maple will convert the expression to an operator of $x$. 3 Right-click any part of the blue output; in the context-sensitive menu that appears, select Assign to a Name. 4 A dialog box appears; enter the name $f$. Click OK. 5 To see what $f$ does, enter $f\left(1\right)$ and press Ctrl + = to evaluate it in-line. As you can see, Maple evaluates the expression ${x}^{2}-1$ at $x=1$, which yields ${1}^{2}-1=0$.

 Related Topics The How Do I... topics cover the essentials for doing mathematics in Maple. Learn more about available tools and features, such as palettes and context-sensitive menus. Refer to Help>Quick Reference for basic Getting Started tips.