Tikal-25 Manual - Arithmetic Functions

The calculator observes priority of multiplication/division over addition/substraction. Simple addition, substraction, multiplication or division operation may be keyed in just as the problem is stated. Parentheses are available to override the natural order of execution.

The displayed result of any calculations may be used directly as the input of a following operation. As in all such situations, the internally held value with full accuracy is used instead of the possibly rounded display value.

The calculator uses standard algebraic priority rules to process a chain of entered operations. The rules used prioritize operations in the following sequence (highest priority first):

1. All special functions that work directly on the displayed value such as trigonometric, logarithmic, square and square root, percentage and reciprocal.
3. Exponentiation (Y^x and root (^x√y)).
4. Multiplication and Division
5. Addition and Subtraction
6. Equals

2 × 5 + 3 × 4 is 22, not 52

2 × 5 + 3 × 4 = 22

This is the calculation of 7 × 5² + sin 17:

Entry	Press	Display	Explanation
7	×	7	7 ist stored on the numeral stack, × is stored on the operational stack
5	x2	25	Square executes immediately on the current value
	+	175	× has higher priority than +, so 7 and × are pulled from the stack and processed against 25 as second argument. The result and + are put on the stack.
17	sin	0.2923717	sin is executed immediately on the displayed value
	=	175.29237	= processes all pending operations, which pulls the result and + from the stack and performs the operation with the sin result as second argument.

This way, for example sums of products can be calculated directly entering the problem as written. In case of more complicated problems or if you are unsure about the priority of any particular operation, you can use parentheses to clarify the sequence.

Whenever an expression can not be entered directly using the built-in algebraic priority rules or you are in doubt about about how the rules will be applied to your problem, parentheses can be used.

If you press ( 7 + 8 ), the result 15 is immediate displayed and will be used if you then press ×, instead of prioritizing the multiplication operation. This way, the algebraic rules are limited to each set of parentheses that are used in a problem. Whenever the calculator has all necessary information to complete any operation, considering the implicit priority rules and parentheses, the operation will be carried out and the result is displayed. When a parenthesis is colsed, all operations back to the opening of the parenthesis are processed.

To calculate with constants, first enter the desired operation out of +,-,×,÷,y^x,INV y^x, then press 2nd K, enter the desired constant number and press =.

4" = 10.16 cm

4 × 2nd K 2.54 = 10.16

7 = 17.78

2 = 5.08

4 y^x 2nd K 3.2 +/- = 0.6484198

7 = 0.5443859

2 = 0.8052452