While educators and policymakers debate whether 8th graders can be readied to learn algebra, Sigrid B. Frawley sits in front of her kindergartners with a magic bag. She puts three tokens in the bag ...
American Journal of Mathematics, Vol. 120, No. 6 (Dec., 1998), pp. 1277-1287 (11 pages) A theorem of Cassidy states that any Zariski closed differential algebraic subgroup of a simple linear algebraic ...