化简x2x-1+x1-x的结果是( ) A.x+1 B.x-1 C.-x D.x
问题描述:
化简
+x2 x-1
的结果是( )x 1-x
A. x+1
B. x-1
C. -x
D. x
答
+x2 x-1
=x 1-x
-x2 x-1
x x-1
=
x2-x x-1
=
x(x-1) x-1
=x,
故选:D.