原式=2001÷[2001x2002 +2001)/2002]+ 1/2003
=2001÷ [2001x(2002+1)/2002] +1/2003
=2001÷ [2001x2003/2002] +1/2003
=2001X2002 /2001x2003 +1/2003
=2002/2003 +1/2003
=1
原式=2001÷[2001x2002 +2001)/2002]+ 1/2003
=2001÷ [2001x(2002+1)/2002] +1/2003
=2001÷ [2001x2003/2002] +1/2003
=2001X2002 /2001x2003 +1/2003
=2002/2003 +1/2003
=1