$@Mốc$
Ta lấy MTC: $10x.(x-2y).(x+2y)$
+)`\frac{7}{5x}`
= `\frac{7.2x.(x-2y).(x+2y)}{10x.(x-2y).(x+2y)}`
= `\frac{14.(x-2y).(x+2y)}{10x.(x-2y).(x+2y)}`
+)`\frac{4}{x-2y}`
= `\frac{4.10x.(x+2y)}{10x.(x-2y).(x+2y)}`
= `\frac{40x.(x+2y)}{10x.(x-2y).(x+2y)}`
= `\frac{40x^{2}+80xy}{5x}`
+)`\frac{x-y}{8y^{2}-2x^{2}}`
= `\frac{x-y}{2.(4y^{2}-x^{2}}`
= `\frac{y-x}{2.(x^{2}-4y^{2})}`
= `\frac{5x.(y-x)}{10x.(x-2y).(x+2y)}`
= `\frac{5xy-5x^{2}}{10x.(x-2y).(x+2y)}`
$#chucbanhoctotnhe;333$