若x,t∈{x∈R|x>0},切x+y>2,求证:(1+x)/y
若x,t∈{x∈R|x>0},切x+y>2,求证:(1+x)/y
已知x,y∈R*,x+y=1,求证2/x+1/y≥3+2根号2
x,y∈R.x+y=1 求证(x+2²+(y+2)²≥25/2
若全集I={(x,y)|x,y∈R},集合M={(x,y)|(y-3)/(x-2)},N{(x,y)|y=x=1},则(
定义在R上的函数f(x),对任意的x、y∈R,有f(x+y)+f(x-y)=2f(x)f(y),且f(0)不等于1,求证
x,y属于R*,且x+y=1,求证:(1)(x+1/x)(y+1/y)≥25/4 (2)(x+1/x)^2+(y+1/y
设x,y,z∈,R求证:x²+xz+z²+3y(X+y+z)≥0
已知x,y∈R+,且x+y=1,求证:xy+1xy≥174
已知x.y∈R,求证x2+y2+1≥x+y+xy
x,y∈R+,1/x+1/y=4,则x+2y最小值?
已知x+2y=1,x,y∈R,求x^2y的最大值
已知f(x)的定义域为R,对任意x,y∈R,有f(x+y)+f(x-y)=2f(x)f(y),且f(0)≠0.求证:y=