3/2-3/4-3/8-3/16-3/32-3/64
=3/2-3/4-3/8-3/16-3/32-3/64-3/64+3/64
=3/2-3/4-3/8-3/16-3/32-3/32+3/64
=3/2-3/2+3/64
=3/64