[求助] SOS.....数学盲求助数学题

111......1×  999.,,,..9
┖2002个┚   ┖2002个┚
=111.......1× (100........0 - 1)
  ┖2002个┚     ┖2002个┚
=111.......100..........0-111.......1
  ┖2002个┚┖2002个┚  ┖2002个┚
=111........10888.......89
   ┖2001个┚  ┖2001个┚.