已知圆x^2+y^2+2x-6y+1=0与x^2+y^2-4x+2y-11=0,求两圆的公共弦所在的直线方程及公共弦长

已知X*X+Y*Y+6X-8Y+25=0 求（Y/X)+(X/Y)-2=? 已知：2x+y=6,x-3y=1 求7y(x-3y)(x-3y)-2(3y-x)(3y-x) 已知x,y满足约束条件：x-y+1>=0,x+y-2>=0,x 已知x>0,Y>0,如何证x^2/y+y^2/x>=x+y 已知x求^2+y^2-6x-8y+25=0求1/x-y /x+y/x^4-y^4 已知x^2+y^2+13-4x+6y=0,求(2x-y)^2-2(2x-y)(x+2y)+(x+2y)^2 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 已知x^2+y^2-8x+12y+52=0 ,求1/2x-1/x-y(x-y/2x-x^2+y^2) 已知x^2+y^2-8x+12y+52=0 ,求1/2x-1/x-y(x-y/2x-x^2+y^2) 已知x^2+2x+y^2-6y+10=0 求（x+y)^2 mathematica软件,已知y[x],Y=f1(x),X(x)=f2(x),如何plot Y[X]?y[x_] := x + 9.81/2*x*xk=1X[x] = x - k*y'[x]/(1 + (y'[x])^2)^0.5Y[x] = y[x] + k/(1 + (y'[x])^2)^0.5Plot[{y[x],Y[X],},{x,0,2}] 已知(x+y)^2-2x+2y+1=0,则(x+y)^999= 已知集合A={(x,y)|2x-y+2>=0,x-2y+1 已知：x^2+y^2+4x-6y+13=0,求x^y值. 已知x^2-6xy+9y^2=0,求(x-y)/(x+y) x>0 y>0已知x+2y=1求 1/x+y/1最小值 已知x²+y²+2x-6y+10=0,则x+y= 已知：x²y²-2x+6y+10=0则x+y=