y=(1/2) ^(√-x^2+2x+8)的单调减区间是?

x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 先化简 再求值 (2x-y)(y+x)-(x-2y)(2y+x)-(-3y+x)^2其(√x+1)+y^2+4=-4y [(2x-y)^2-y(y-4x)-8x]其中x=-1/2 9y=3x-(x-1),4(x+y)-(2x+4)=8y y=2x+√(1-x) 【2(x-y)(x-y)(x-y)-8(x-y)(x-y)(x+y)+6y(x-y)(x-y)]/2(x-y)(x-y) 若√x-1-√1-x=(x+y)²先化简再求值：（1/2x）-(1/x+y)[x²-y²+(x+y/2x] [(2x+y)²-y(y+4x)-8x】/4x,其中x=-1,y=2005 急 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) x+y=1 5x-2y=8 3x-y=7 2x-y=3x表示y和用y表示x 若x-y=1 化简（x+y)(x^2+y^2)(x^4+y^4)(x^8+y^8)(x^16+y^16) 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=1 ,xy=-6{x(2x-3)=0,y=x²-1{(3x+4y-3)(3x+4y+3)=0,3x+2y=5{(x-y+2)(x+y)=0,x²+y²=8{(x+y)((x+y-1)=0,(x-y)(x-y-1)=0 【2(x-y)^3-8(x-y)^2(x+y)+6y(x-y)^2】/2(x-y)^2= 2y(x+二分之一y)-[(x+y)(x-y)+2y(y+x)],其中|x-1|=2 （x-y)(x+y)-(x+y)^2+2y(y-x),其中x=1,y=3.