y/(2x^5) 和 y/(5x^2) 的最简公分母:(10x^5)
x/2ab 2/3b^2 y/9a^2b 的最简公分母:(18a^2b^2)
z / (x^2y) x / y^2 yz / x^2y^2 x^3 / x^2y^2
5 / 8xy^2 y/3x^2 15x / 24x^2y^2 8y^3 / 24x^2y^2
2 / xy^2 3 / 2xy 1/5x^2y 20x / 10x^2y^2 15xy / 10x^2y^2 2y / 10x^2y^2
1/2(x+1) x/3(x+1) : 3 / 6(x+1) 2x / 6(x+1)
x/(x+2) 3/(x^2-4) : x(x-2) / (x^2-4) 3/(x^2-4)