求x^2+x^2y^2-y^2=1 在（1,1）处的切线方程和法线方程

求y =2^x -1/x+1在x x+2y=2x+y+1=7x-y 求：2x-y? (x-y)/(x+y)=3求( 3x-2y-1)/(x+y-5) 若x*x+y*y=x+y-1/2,求x,y的值如题 已知x+y=a,2x-y=-2a,求[（x/y-y/x)/(x+y)-x(1/x-1/y)]/[(x+1)/y]的值 若2/x-1/y=3,求[y/x-y/x-y(x-y/x-x+y)]/x-2y/x的值 {(x+y)/2+(x-y)/3=1,(x+y)-5(x-y)=2.求x=?,y=? x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 M(x,y)在圆x^2+y^2=1上移动,求点Q(x(x+y),y(x+y))的轨迹 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) x+y=1,xy=-1/2,求x(x+y)(x-y)-x(x+y)2 已知x-y=1,求[(x+2y)^2+(2x+y)(x-4y)-3(x+y)(x-y)]除以y的值大神们帮帮忙 已知：2x+y=6,x-3y=1 求7y(x-3y)(x-3y)-2(3y-x)(3y-x) 已知:【(x²+y²)-(x-y)²+2y(x-y)】/4y=1,求4x/4x²-y²-1/2x+y 已知x-y=1,求[(x+2y)²+(2x+y)(x-4y)-3(x+y)(x-y)]÷y的值 求(1+y)-2x(1+y)+x(1-y) y=2x*arctan(y/x),求y‘’ 已知x-y=3,求[（x+y)(x-y)-(x-y)^2+2y(x-y)]除以的值