(1/x-y-1/x+y)÷2y/x²-2xy+y²,其中x=√2+1,y=1-√2
先化简,再求值(x-y/x+y)^2÷(y-x/x^2+2xy+y^2)^2*1/x+y,其中x=-4,y=1
先化简再求值 [(1/(x-y)+1/(x+y)]-【2y/(x的平方-2xy+y的平方)】 其中x=1+√2,y=1-
[(x-2y)²-4y²+2xy]÷2x,其中x=2,y=1
[(x-√2y)(x-√2y)-(x-√2y)²+4y(y-x²)]÷2xy 其中x=√2-1/1,
[(y-2x)(-2x-y)-4(x-2y)²]*2y,其中x=1,y=2
先化简再求值(x-y/1-x+y/1)÷x平方+2xy+y平方/2y,其中x=根号3+2,y=根号3
先化简,再求值,x分之x-y÷(x-x分之2xy-y²)其中x=2,y=-1
x+y)(x-y)+(x-y)^2-(6x^2y-2xy^2)/2y,其中x=-2,y=1/3
【(1)/(x-y)+(1)/(x-y)】÷(2x)/(x²-2xy+y²)
先化简再求值:xy^3÷(-xy)+(x+2y)(x-2y),其中x=根号2,y=1
化简求值3x[xy-2x(y-2x)]+3y(x²-y²),其中x=-1,y=2
数学题化简再求值(1/x-y+1/x+y)÷x^2 y^2/x^2-y^2,其中x=3,y=-√2