Math Seminars

The Grand Rapids Community College Mathematics Department is pleased to announce that it will host its first Mathematics Seminar of 2019-2020 on Wednesday, September 18, 3-4 PM in 101 Cook.    

Our speaker is GRCC mathematics instructor Sang Lee.  For the title and abstract of his talk, please see below.

Refreshments will be served at 2:45 PM.

 

Some Irrational Numbers

In textbooks for intermediate algebra, college algebra, trigonometry, and precalculus, it is common to find the directions for exercises such as “Solve each equation.  If the answer is not exact, round to four decimal places.”, or “Solve each equation.  Give irrational solutions as decimals correct to the nearest thousandth.” 

Do students know whether a solution they obtained is rational or irrational?  Would students recognize an irrational number when they see it?  Technology does not help as a graphing calculator can display only a finite number of digits and, at times, a calculator can mislead students in determining irrationality of a number.

In this talk, we will review some common irrational numbers that students may encounter in a course mentioned above.