0

Am doing self--study from the book : The Shape of Algebra in the Mirrors of Mathematics, by Gabriel Katz, Vladimir Nodelman; and have issues. Luckily, the concerned first chapter is freely accessible here. The s/w Visumatica basically is an openGL based one.

On pg.#5, question #1 is not clear in terms of logic implied, as need consider only one point to draw a rectangle and the other point is given by origin(0,0). So, how it is possible that some points are excluded. It is not stated that only first quadrant points are needed. So, the logic is not clear. Please help.

The image for the stated file of Visumatica is here

*Addendum * For the question #2 of the book on page #5-6, have files for Visumatica given as Ex 1.1-2a, Ex 1.1-2b, Ex 1.1-2c.

jiten
  • 4,524
  • For a rectangle, if one point is (0,0) only one more point need be specified to define it, it's diagonal (a,b). From this the other points are (0,b) and (a,0). – Phil H May 17 '18 at 22:27
  • @PhilH Agreed, but which points are to be excluded is what the question asks. Also, I feel it is a theoretical question, based on some 'missing' constraints , that the book fails to specify in the text before. Do you imply that the points on any of the axis are excluded as then rectangle cannot be formed. – jiten May 17 '18 at 22:36
  • 1
    The diagonal is the only point needed because a vertical line dropped to the x axis, and a horizontal line to the y axis defines the rectangle. Exclude the points on the x and y axis. This is discussed in the text prior to exercise 1.1. Of course it assumes a specific orientation of the rectangle. – Phil H May 17 '18 at 22:48

0 Answers0