18 tháng 2 2022 lúc 20:02
sửa đề \(\dfrac{2}{x}+\dfrac{1}{5}=\dfrac{1}{y}\Rightarrow10y+xy=5x\Leftrightarrow10y+xy-5x=0\)
\(\Leftrightarrow x\left(y-5\right)+10\left(y-5\right)+50=0\)
\(\Leftrightarrow\left(x+10\right)\left(y-5\right)=-50\)
\(\Rightarrow x+10;y-5\inƯ\left(-50\right)=\left\{\pm1;\pm2;\pm5;\pm10;\pm25;\pm50\right\}\)
| x+10 | 1 | -1 | 2 | -2 | 5 | -5 | 10 | -10 | 25 | -25 | 50 | -50 |
| y-5 | -50 | 50 | -25 | 25 | -10 | 10 | -5 | 5 | -2 | 2 | -1 | 1 |
| x | -9 | -11 | -8 | -12 | -5 | -15 | 0 | -20 | 15 | -35 | 40 | -60 |
| y | -45 | 55 | -20 | 30 | -5 | 15 | 0 | 10 | 3 | 7 | 4 | 6 |
Đúng 2
Bình luận (0)
