问题
填空题
已知整数x、y满足:1<x<y<100,且x
则:
|
答案
∵x
+yy
-x
-2009x
+2009y
=20092009xy
∴
(xy
+x
)-y
(2009
+x
)+y
-2009xy
=020092
(
+x
+y
)(2009
-xy
)=02009
∵1<x<y<100
∴
-xy
=02009
∴xy=2009=7×7×41=49×41
∵整数x、y满足:1<x<y<100
∴x=41,y=49
∴
=x+y+10
=41+49+10
=10.100
故本题答案为:10.