abc-[2ab-(3abc-bc)+4abc]其中a=2b=-1/2c=-1

问题描述:

abc-[2ab-(3abc-bc)+4abc]其中a=2b=-1/2c=-1

a=2b=-1/2c=-1
a=-1 b=-1/2 c=2
abc-[2ab-(3abc-bc)+4abc]
=abc-(2ab-3abc+bc+4abc)
=abc-2ab+3abc-bc-4abc
=-2ab-bc
=-1/2-1
=-3/2

abc-[2ab-(3abc-bc)+4abc]
=abc-2ab+3abc-bc-4abc
=-2ab-bc
=-2*2*(-1/2)-(-1/2)(-1)
=2-1/2
=3/2