求方程6y*2-2xy+7y-x+17=0的正整数解

求方程6y*2-2xy+7y-x+17=0的正整数解 求方程(x+y)/(x^2-xy+y^2)=3/7的整数解1 求方程xy-2x-2y+7=0(x≤y)的整数解 已知X+y=6,xy=7 求x^2y+xy^2=已知X+y=6,xy=7 x^2y+xy^2 求方程xy-x-y=2的整数解 已知1/x-1/y=2,求3x+7xy-3y/2x-3xy-2y答案是1/x-1/y=2(y-x)/xy=2 得：x-y=-2xy(3x+7xy-3y)/(2x-3xy-2y)=[3(x-y)+7xy]/[2(x-y)-3xy]=(-6xy+7xy)/(-4xy-3xy)=xy/(-7xy)=-1/7 谁能帮我解释一下=[3(x-y)+7xy]/[2(x-y)-3xy]=(-6xy+7xy)/(-4xy-3xy) 是怎 函数y=f(x)由方程xy^2+sinx=e^y,求y′ 1-2/x+y=xy,4y+6x=xy.求xy的解? 方程x^3+y^2-xy^3=2确定y是x的函数y=(x)、求y' 求方程xy-2x-3y=5的整数解还有6xy+4x-9y-7=0 x+y=8,xy=-2,求(5xy+4x+7y)+(6x-3xy)-(4xy-3y)的值 不解方程：2x+y=7/2005,x+3y=2005/8,试求代数式6x^2+21xy+9y^2的值. 若实数XY满足方程X²-XY-2Y²+5x-4y+6=0试求x²+y²的最小值 求方程xy-2x-2y=6的所有正整数解 求方程4xy-5x+6y=15的所有正整数解 已知xy^2=-6,求-xy(x^3y^7-3x^2y^5-y）的值 已知xy=-2,x-y=3,求（x+y)（x-y)-y^2+（x-y)^2-（6x^2y-2xy^2)÷2y 诺x+y=6,xy=4 求(5x-4y-3xy)-(8x-y+2xy) 已知xy/x+y=6,求3x-2xy+3y/-x+3xy-y的值.