Education Technology

Solution 11840: Implicit Multiplication on the TI-89 Family, TI-92 Family, and Voyage™ 200.

Do the TI-89 family, TI-92 family, and Voyage 200 recognize implicit multiplication?

The TI-89 family, TI-92 family, and the Voyage 200 recognize implied multiplication, provided it does not conflict with a reserved notation.

The following are examples of how the implied multiplication is interpreted on the TI-89 family, TI-92 family, and Voyage 200 for certain expressions:

1. Valid implied multiplication:

• 2p is interpreted as 2 * p.
• 4sin(46) is interpreted as 4 * sin(46).
• 5(1+2) is interpreted as 5 * (1+2).
• [1,2]a is interpreted as [a,2a].
• 2(a) is interpreted as 2 * a.

2. Invalid implied multiplication:

• xy is interpreted as a single variable named xy.
• a(2) is interpreted as a function call.
• a[1,2] is interpreted as a matrix index to element a[1,2].

Note: Another example, x (a+b), is not read as multiplication. The only significance that the parser gives to white space is that it terminates tokens. Thus, abcd is a single name, but ab cd are two separate names, because the space caused the name parsing algorithm to stop after the b.

Spaces do not directly create implied multiplication. Implied multiplication occurs when two valid factors are found in succession without any other binary operator between them. When the next non-blank following a valid name is a left parenthesis, the name is assumed to be a function/program reference.

Please see the TI-89 family, TI-92 family and Voyage 200 guidebooks for additional information.