问题
填空题
已知x-1与y+1互为负倒数,则 y-1-x-1=______.
答案
∵x-1与y+1互为负倒数,
∴(x-1)•(y+1)=-1,
∴xy=-(x-y),
∴原式=
-1 y
=1 x
=x-y xy
=-1.x-y -(x-y)
故答案为:-1.
已知x-1与y+1互为负倒数,则 y-1-x-1=______.
∵x-1与y+1互为负倒数,
∴(x-1)•(y+1)=-1,
∴xy=-(x-y),
∴原式=
-1 y
=1 x
=x-y xy
=-1.x-y -(x-y)
故答案为:-1.