src/HOL/Integ/IntRing.ML
author wenzelm
Thu Jan 23 14:19:16 1997 +0100 (1997-01-23)
changeset 2545 d10abc8c11fb
parent 2281 e00c13a29eda
child 3018 e65b60b28341
permissions -rw-r--r--
added AxClasses test;
     1 (*  Title:      HOL/Integ/IntRing.ML
     2     ID:         $Id$
     3     Author:     Tobias Nipkow and Markus Wenzel
     4     Copyright   1996 TU Muenchen
     5 
     6 The instantiation of Lagrange's lemma for int.
     7 *)
     8 
     9 open IntRing;
    10 
    11 goal thy "!!i1::int. \
    12 \  (sq i1 + sq i2 + sq i3 + sq i4) * (sq j1 + sq j2 + sq j3 + sq j4) = \
    13 \  sq(i1*j1 - i2*j2 - i3*j3 - i4*j4)  + \
    14 \  sq(i1*j2 + i2*j1 + i3*j4 - i4*j3)  + \
    15 \  sq(i1*j3 - i2*j4 + i3*j1 + i4*j2)  + \
    16 \  sq(i1*j4 + i2*j3 - i3*j2 + i4*j1)";
    17 br Lagrange_lemma 1;
    18 qed "Lagrange_lemma_int";