y=√2x-5 + √5-2x-3,则2xy等于多少 每一项都包括在根号里面的,注意

若x>0,y>0,且√x(√x+√y)=3√y(√x+5√y),求2x+2√x*√y+3y/x-√x*√y+y 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) 已知实数x,y满足x=√(9-x+2y)+√(3x-6y-27)+5,则-2x-y的立方根为 y=(3x^2-x√x+5√x-9)/√x 求导 √x(√x+2√y)=√y(6√x+5√y,求x-3√xy+2y/x+√xy-6y 若2x-3y+4=0则x（x*x-1)+x(5-x*x)-6y+7 xy²/(x²y-y) × x²/(x²+x)=(x²-3x)/(x²-5x) × 2x-10/(x²-6x+9)=化简求植x²-1/(x²-x-2)除以x/2x-4,其中x=1/2[x-x/(x+1)]除以[x/(2x-4)] ,其中x=√2+1 已知4x²+y²-4x-6y+10=0求（2/3x（√9x）+(y²√x/y³)×(x²√1/x×5x√y/x)的值 已知4x²+y²-4x-6y+10=0求（2/3x（√9x）+(y²√x/y³)-(x²√1/x-5x√y/x)的值 已知4x²+y²-4x-6y+10=0,求[(2/3)x√(9x)+y²√(x/y³)-(x²√(1/x)-5x√(y/x)的值 若3x-5y=0,则x+y/x=（）,x-y/y=（）,2x-3y/2x+3y=( ) y=(3x-1)/(x+1) (x>=5)值域 y=x-√(1-2x)值域 (√x-2)+x-y-(√2-x)=5 x+y/2+x-y/6=5 2(x+y)-3(x-y)=-2 3(x+y)+2(x-y)=36 4(x+y)-5(x-y)=2 若√(3x+5y-2-m)+√(2x+3y-m)=√(x-199+y)*√(199-x-y),则m为? (x-y)/(x+y)=3求( 3x-2y-1)/(x+y-5) 4(x-y)-3(x-y)=9 5(x-y)+2(x-y)=11