Calculating partial derivatives and evaluating them at a point can be done with just the Context Panel system.
Context Panel
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Control-drag the expression for and press the Enter key.
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Context Panel: Differentiate≻With Respect To≻ (or )
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Context Panel: Evaluate at a Point (see Figure 4.1.3(a)).
(Context Panel: Simplify≻Simplify)
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Figure 4.1.3(a) Evaluate at
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Defining as an expression allows its partial derivatives to be calculated and evaluated at a point via some of the palette templates, allowing for a more natural notation to be displayed.
Define as an expression
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Control-drag the expression for .
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Context Panel: Assign to a Name≻
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Obtain and
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Calculus palette: First-partial operator
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Context Panel: Evaluate and Display Inline
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Calculus palette: First-partial operator
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Context Panel: Evaluate and Display Inline
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Obtain and
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Expression palette: Evaluation template
Calculus palette: First-partial operator
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Context Panel: Evaluate and Display Inline
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Expression palette: Evaluation template
Calculus palette: First-partial operator
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Context Panel: Evaluate and Display Inline
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Context Panel: Simplify≻Simplify
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A very high degree of notational faithfulness can be obtained by defining subscripts as operators.
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In the present context, the expression for is already assigned to the name .
Were this not so, the expression would have to be assigned to a name, preferably, .
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Define the functions and
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Calculus palette: First-partial operator
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Context Panel: Assign Function
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Obtain and
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Obtain and
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