Mathematics - Abstract Algebra - Rings and fields - Classify Algebraic Structures

Present 10 structures on cards. Student sorts into: Group only, Ring, Integral Domain, Field. (1) (ℤ,+,×) - Ring/integral domain. (2) (ℚ,+,×) - Field. (3) (ℤ₄,+,×) - Ring (2·2=0, zero divisor). (4) (ℤ₅,+,×) - Field. (5) (ℤ₆,+,×) - Ring (zero divisors). (6) (2ℤ,+,×) even integers - Ring (no unity!).