Technology Tips: TI-Nspire Calculators: Better but Still Not Perfect

• Published in: The Mathematics teacher 2009-02, Vol.102 (6), p.464-467
• Main Authors: Bossé, Michael J., Adu-Gyamfi, Kwaku
• Format: Article
• Language: English
• ISSN: 0025-5769; 2330-0582
• DOI: 10.5951/MT.102.6.0464

Texas Instruments calculators are ubiquitous in today's K–16 mathematics classrooms, so mathematics instructors must understand the necessary programming limitations of each calculator. Previous generations of TI graphing calculators (the TI-89 and TI-92 calculators) produced some graphical and symbolic errors (documented in BossÉ and Nandakumar [2003, 2004] and Marchand and others [2007]). Fortunately, TI has now remedied most of these errors in its new graphing calculators, the TI-Nspire and the TI-Nspire CAS. Although the TI-Nspire still incorrectly graphs some functions seen only in graduate mathematical studies, it now renders correctly almost all functions that mathematics students encounter through precalculus. Overcoming these programming difficulties was no small matter, and the corrected results are a testament to the more sophisticated programming in these new TI-Nspire calculators. In this article, we will look at some functions that previously did not graph correctly on the TI-89 and TI-92 because of programming constraints, some functions that still do not graph correctly on the TI-Nspire, and improvements in how the TI-Nspire CAS handles the rewriting of symbolic expressions.