Using Parentheses


At times, you may want an expression evaluated differently from the normal order of evaluation. Using parentheses lets you control the order of evaluation. You should use parentheses if you have any doubts about the way the calculator will evaluate an expression.



Effect of Parentheses

Using parentheses enables you to give priority to operations within an expression. When you enclose a portion of an expression within parentheses, that portion is evaluated separately.

Although some mathematics expressions often use parentheses to imply multiplication, the RPD-95 requires that you include the [ × ] key in the calculation. For example, you must enter 7( 3 + 5 ) as 7 × ( 3 + 5 ).

Example

Calculate 7 × ( 3 + 5 ).

Procedure

Press

Display

Clear display[ CLEAR ]D_McSSNB
Begin pending multiplication7 [ × ]D_23laWK
Enter and evaluate parenthetical expression[ ( ] 3
[ + ]
5 [ ) ]
D_CF4v5F
Complete pending operation2 [ = ]D_AQaaWF


If this expression were entered without parentheses, the AOS feature would complete the multiplication ( 7 × 3 ) before the addition ( + 5 ), producing an incorrect result of 26.

Levels of parentheses

You can use up to 15 levels of parentheses. This give you the capability to enter more complex expressions.

Example

Calculate 2 × ( 2 × ( 2 × ( 2 × ( 2 × ( 2 + 3 ) + 2 ) + 2 ) ) ).

Procedure

Press

Display

Clear display[ CLEAR ]D_McSSNB
Enter pending multiplications2 [ × ]
[ ( ] 2 [ × ]
[ ( ] 2 [ × ]
[ ( ] 2 [ × ]
[ ( ] 2 [ × ]
D_EqUCXs
Enter ( 2 + 3 )[ ( ] 2 [ + ]
3 [ ) ]
D_3p85su
Evaluate ( 2 × 5 + 2 )[ + ] 2
[ ) ]
D_Lw7tCu
Evaluate ( 2 × 12 + 2 )[ + ] 2
[ ) ]
D_an8Hlf
Evaluate ( 2 × 26 )[ ) ]D_FhuOuy
Evaluate ( 2 × 52 )[ ) ]D_91KUkV
Evaluate 2 × 104[ = ]D_Loo8PB


It is not necessary to press [ ) ] when it is at the end of a calculation. Pressing [ = ] automatically closes all open parentheses, evaluates the expression in the proper order, and displays the end result. However, if you want to see the intermediate result of a parenthetical expression, you must use the [ ) ] key.


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