从圆X^2-2X+Y^2-2Y+1外一点P（3.2）向这个圆作两条切线.这两切线夹角的余弦值为多少?

从圆x^2+y^2-2x-2y+1=0外一点P(2,3),引圆的切线,求切线方程 从圆x^2+y^2-2x-2y+1=0外一点(3,2)向这个圆做两条切线,则两切线夹角的余弦值 圆C：x^2+y^2+2x-4y+3=0,若不过原点的直线l与圆C相切,在x,y轴上截距相等,求直线l.从圆C外一点P(x,y)向...圆C：x^2+y^2+2x-4y+3=0,若不过原点的直线l与圆C相切,在x,y轴上截距相等,求直线l.从圆C外一点P(x,y) x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 [(-x-y)(-x+y)-(x+y)^2-x(y-y^2)}÷1/2y (x+2y)²-2（x-y)(x-y)+2y(x-3y)帮忙化简下,准确一点哦, 化简y(x+y)+(x+y)(x-y)-x^2 过圆x*x+y*y-2x+4y+1=0外一点p(0-4)向圆引切线,求切线方程 利用因式分解求x(x+y)(x-y)-x(x+y)^2的值,其中x+y=1,xy=1/2.完整一点 (x+y)(x-y)-(x-y)^2如题 (x+y)(x-y)-(x-y)^2 从圆外一点P(x.,y.）引圆x^2+y^2=r^2的两切线,则切点弦的方程是（过程谢谢） 【2(x-y)(x-y)(x-y)-8(x-y)(x-y)(x+y)+6y(x-y)(x-y)]/2(x-y)(x-y) 因式分解x(x+y)(x-y)-x(x+y)^2 从M={(x,y)||x-2|+|y-2| 1、y-x/x²-y²2、(x-y)(y-z)(z-x)/(z-y)(y-x)(x-z) (x-y)(2x-y-1) (x/x+y-x/y-x-2xy/x.x-y.y)/(1/x-1/y) 分式化简 [(x-y)^2-(x+2y)(x-2y)]/y