规定X@y=Xx(X+1)x(X+2)x.x(X+y-1),如2@4=2x3x4x5已知n+1/n@3=1/575,求自然数n

7/xx+x+1/xx-1=2/xx-x (x-y)(x+y)(xx-yy)=? 规定X@y=Xx(X+1)x(X+2)x.x(X+y-1),如2@4=2x3x4x5已知n+1/n@3=1/575,求自然数n [2x-(x+y)(x-y)](yy-xx) x y x+yy x+y xx+y x y x y x+yy x+y xx+y x y 已知x(x-1)-(xx-y)=-3求xx+yy-2xy 已知x（x+1)-(xx+y)=3,求(xx+yy)/2-xy的值 x(x+1)-(xx+y)=-3,求(xx+yy)/2-xy的值 题目是 （1） XX*X=XX X*X=XX X为未知数分别将1到9的9个数填入不能重复 *为乘号 (2)XX/X=X X/X=XX/ X X为 [(x-y)²+（x+y）(x-y)]/2xx=3,y=-1.5 求一个数独答案X X X 9 X X X 8 2 X 6 3 X X 1 4 X 99 X 8 X X X X X XX X X 6 7 X 3 X XX 4 6 X 5 X 2 9 XX X 7 X 2 3 X X XX X X X X X 7 X 17 X 4 3 X X 6 2 X6 3 X X X 7 X X X XX-YY/(X-Y)(X-Y)约分 小数奥数网xx(x +1)x(x+ 2)x(x +3)=360怎样算? 解九宫格题目（X为未知数）9 X 2 X 7 X 8 X XX X 4 X X 9 X 6 X1 3 X 5 X X X X 24 X X 8 5 X X 1 XX 8 9 4 X 1 6 7 XX 1 X X 3 6 X X 88 X X X X 2 X 3 6X 5 X 6 X X 9 X XX X 7 X 4 X 2 X 1 1.不等式|x|*(1-2x)>0的解集为多少?2.函数y=3x/x^2+x+1 (xx^2是X的平方 x+(9-8-y)=10 y+y-(9-8-y)=2 x-y=xx-9.9x xy=11y-1 y=? x=? x+y-xy=?x+(9-8-y)=10y+y-(9-8-y)=2x-y=xx-9.9xxy=11y-1 y=?x=?x+y-xy=? y=log5(x*x-4x-12)求它的定义域 xx-4x-12>0 (x-6)(x+2)>0 => x>6 或 x