\(\frac{1}{x}=\frac{1}{6}+\frac{3}{y}\) <=> \(\frac{1}{x}=\frac{y+18}{6y}\) (x, y khác 0)
=> \(x=\frac{6y}{y+18}=\frac{6y+108-108}{y+18}=\frac{6\left(y+18\right)-108}{y+18}\)
=> \(x=6-\frac{108}{y+18}\)
=> Để x nguyên thì 108 chia hết cho y+18 => y+18=(-2,-3,-4,-6,-9,-12,-27,-36,-54,-108,2,3,4,6,9,12,18,27,36,54,108)
=> y và x
\(\frac{1}{x}\)= \(\frac{1}{6}\)+\(\frac{3}{y}\)
= 6+3 = 1+y
= 9 =1+y
y = 9-1
y = 8
\(\frac{1}{x}\)= 8
x = 1.8
x = 8