HP 33s Scientific manual Types of Equations, Evaluating Equations

Keys:Display:Description:

H /ºº 1!.2

bº 1!.2-¾

bb/ºº 1!.2¾

‘/ºº 1!.2

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Shows the current equation in the equation list.

Turns on Equation–entry mode and shows the "¾" cursor at the end of the equation.

Deletes the number 25.

Shows the end of edited equation in the equation list.

Leaves Equation mode.

Types of Equations

The HP 33s works with three types of equations:

„Equalities. The equation contains an "=", and the left side contains more than just a single variable. For example, x2 + y2 = r2 is an equality.

„Assignments. The equation contains an "=", and the left side contains just a single variable. For example, A = 0.5 ⋅ b ⋅ h is an assignment.

„Expressions. The equation does not contain an "=". For example, x3 + 1 is an expression.

When you're calculating with an equation, you might use any type of equation — although the type can affect how it's evaluated. When you're solving a problem for an unknown variable, you'll probably use an equality or assignment. When you're integrating a function, you'll probably use an expression.

Evaluating Equations

One of the most useful characteristics of equations is their ability to be evaluated — to generate numeric values. This is what enables you to calculate a result from an equation. (It also enables you to solve and integrate equations, as described in chapters 7 and 8).

Entering and Evaluating Equations 6–9