Tìm số các cặp số nguyên (x,y) thỏa mãn : 2017xy=x+y
2017xy=x+y
#1
Đã gửi 24-11-2017 - 20:10
#2
Đã gửi 24-11-2017 - 22:14
Ta có: $x+y=2017xy\Rightarrow x=\frac{y}{2017y-1}$
Mà: x nguyên => y chia hết cho 2017y-1
=>2017y chia hết cho 2017y-1
=> 1 chia hết cho 2017y-1
=> $2017y-1\in$Ư(1)={-1;1};
- lquanghng15 yêu thích
It doesn't matter if you're the slowest kid in gym class or the fastest man alive. Every one of us is running, being alive is running, running from something, running to something or someone. And no matter how fast you are. There's some things you can't outrun. Some things always manage to catch up to you.
___ THE FLASH ___
0 người đang xem chủ đề
0 thành viên, 0 khách, 0 thành viên ẩn danh