求12x-1x+y(x+y2x-x-y-1)的值,其中x=l,y=0.-数学

题目简介

求12x-1x+y(x+y2x-x-y-1)的值,其中x=l,y=0.-数学

题目详情

1
2x
-
1
x+y
(
x+y
2x
-x-y-1)
的值,其中x=l,y=0.
题型:解答题难度:中档来源:不详

答案

class="stub"1
2x
-class="stub"1
x+y
class="stub"x+y
2x
-x-y-1)
=class="stub"1
2x
-class="stub"1
x+y
[class="stub"x+y
2x
-(x+y+1)]
=class="stub"1
2x
-class="stub"1
x+y
class="stub"x+y
2x
+class="stub"x+y+1
x+y

=class="stub"1
2x
-class="stub"1
2x
+1+class="stub"1
x+y

=1+class="stub"1
x+y

当x=1,y=0时,原式=1+class="stub"1
1+0
=2.

更多内容推荐