Exercise 23.8 (v)

I was asked in class today about Ex. 23.8 (v) and gave some not so useful advice.  The problem asks you to prove that there is no positive integer solution to x^2 +x +1 =y^2.  There is a simple solution that begins with the observation that any positive solution would satisfy $x < y$, and so $y \ge x+1$ (since $x$ and $y$ are supposed to be integers).

Induction Homework

The homework assignment for Ch. 24 and 25 is now posted:

Exercises 24.10 (i), (ii), (iv), (ix) and 25.7 (ii)

The homework may be turned in at recitation on Thursday.

Please note that there are many more problems in Chapter 24.  It is highly recommend that you work of many of these as you can.  However, only the above problems need to be turned in.