X>0 Y>0证1/x+1/y>=4/(x+y)X>0 Y>0 证1/x+1/y>=4/(x+y)

X>0 Y>0证1/x+1/y>=4/(x+y)X>0 Y>0 证1/x+1/y>=4/(x+y) x>0 y>0 x+y=1 证(x+1/x)(y+1/y)≥25/4 x>0 y>0 x+y=1,4/X+9/y最小值x>0 y>0 x+y=1,求4/X+9/y最小值 {4x-3y-10=0 3x-2y=0,{3x-4(x-y)=2 2x-3y=1,{2(x+y)-(x-y)=3 (x+y)-2(x-y)=1 {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 4x+y-9>=0 ,x-y-1 如果|x-y+1|+y^2-4y+4=0,求出x,y的值 设x大于1,y大于0,x^y+x^-y=2根号二,x^y-x^-y等于? 证明：若x>0,y>0,x+y=1,则（x+1/x)(y+1/y)≥25/4 若x,y满足约束条件,x>=0,y>=0,x-y>=-1,3x+4y x,y>0,且x+2y=1,u=(x+1/x)(y+1/(4y)最小值是: x>0 y>0 x+y=1,4/X+9/y最小值 x>0 Y>0x+y=2求1/x+4/y的最小值 x^2-x+y^2+2y+5/4=0 求x^-1+y^0 3x+4y-5=0 x^2+y^2=1求x.y 已知3x+4y-6x-1-y=0,那么x-y=_______. |x-2y+1|+(x+y-5)²=0,则5x+4y= 已知x,y大于0,x+4y=1,求x*y最大值.