 
Summary: ABSTRACT ALGEBRA:
A Geometric Approach
Theodore Shifrin
Errata and Typographical Errors
p. 17, lines 34. N is the smallest positive integer having . . . . Note, in particular, that N cannot
be prime; now, suppose . . .
p. 18, Exercise 3. gcd(0, m) = m.
p. 18, Exercise 13. µ = ab and ab/d.
p. 21, line 4. Delete ")".
p. 24, line 8. Delete the second "p."
p. 35, Exercise 38. Using e = 101, check that d = 317. In the first line of the table, 1663 should
be 1633. . . . Using the same N and e = 1601, . . . .
p. 39, line 14. . . . a1(ab) = a1 · 0 = 0. . . .
p. 47, line 10. Given n Z, exactly one of the statements
n Z+
, n = 0, or n Z+
is true. (This is called the trichotomy principle.)
line 15. Z+ should be Z+.
line 21. Given x F, exactly one of the statements
x F+
