Graphing Calculators for Math Courses

Students in precalculus and calculus courses may want to have a graphing calculator available, and some instructors do assign homework problems for which a calculator would be useful. 

The policy for calculators at quizzes/exams varies from course to course (or from one exam to the next, depending on the subject matter for the particular test).  Probably you should wait until classes start to find out whether a calculator is important for your course. However, if you want to purchase a calculator before you arrive, then the following information may be useful.

  • Any graphing calculator is acceptable for your personal use in study and on homework assignments. However, some higher-end calculators contain a computer algebra system (CAS) that allows them to perform symbolic manipulations-- for example, to simplify 2*(2*x+1)^2 - 3*(3*x-2)^3 . Calculators containing a CAS (for example, the TI-89, TI-92/TI-92 Plus, Casio FX2, HP-48 and HP-49) are usually not allowed at math quizzes and exams.
  • Some courses might not allow any calculators at exams, or allow only simple scientific calculators just to help with arithmetic.
  • If you need to buy a graphing calculator, or want to upgrade from an older model, the Math Department's recommendation for our courses is the Texas Instruments TI-83 series. The advantage of the TI-83 series is that it has built-in probability distributions that are required in Math 3200 and which students may also find useful in any course containing statistical material. (These distributions can also be downloaded from the web to some other Texas Instruments calculators).  TI-83's do not contain a CAS.

Even if you are fairly familiar with your calculator, do not forget to bring the manual along with you.

A word of caution: do not become overly dependent on your calculator. A calculator can be a very useful tool for complicated calculations, but you should be able to do the basic computations and manipulations in calculus without a calculator--or, at most, just using it to help out with tedious arithmetic (and, not all arithmetic is tedious!).

You are too dependent on your calculator if, for example:
  • You use a calculator when you need to know sin (pi/6) or tan(pi/3) or ln ( e ^ ( -3.9)  ).
  • You consistently use a calculator to get answers in calculations such as 4/7 + 3/8, which can be easily done by hand.  Finding (approximate) decimal answers instead of exact fractions in relatively simple problems generally means that a student uses the calculator too much.
  • You don't know the appearance of simple graphs like y = (x-1)^2, y = cos(2x) + 1, y = 2^(-x), etc. without having your calculator graph them.
  • You find yourself immediately punching buttons on the calculator as soon as you get started on a test. Generally, not many problems on a calculus exam are intended to require a calculator. 

Information for TI-83 use in calculus

If you have a question, please contact Professor Blake Thornton:

blake@math.wustl.edu
(314 )935-6301