求y=(x^2+3x+5)/(x+1) (x>-1)最小值

(x-y)/(x+y)=3求( 3x-2y-1)/(x+y-5) {(x+y)/2+(x-y)/3=1,(x+y)-5(x-y)=2.求x=?,y=? 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) 若2/x-1/y=3,求[y/x-y/x-y(x-y/x-x+y)]/x-2y/x的值 y=(2x*x-2x+3)/(x*x-x+1),求值域? 已知:3x-5y=0,求x/y,x-y/y,x-y/x 用递归法求y=x-(x*x*x/3!)+(x*x*x*x*x/5!)-(x*x*x*x*x*x*x/7!)+. 4x-3y=5 x^2+y^2=1 求x,y 3x+4y-5=0 x^2+y^2=1求x.y x+y=8 2x-y=1 求3x+5y 求值域 1,y=(x+2)/(x*x+3x+6) 2,y=3x/(x*x+4) 求y=(5x-1)/(4x+2) (x y=(X+1)(X+2)(X+3)求导数 求y=(x^2+3x+5)/(x+1) (x>-1)最小值 若x^5+x^4y+x^4+x+y+1=0,且3x+2y=1,求x,y的值 y=x^5+√x+1/x^3 ,求导数结果是y’=2x-5/2x^-7/2-3x^-4,对y求导数 已知x=1/3,y=-1/2,求代数式x-(x+y)+(x+2y)-(x+3y)+(x+4y)-(x+5y)+...-(x+2009y)的值. 已知x=1/3,y=-1/2,求代数式x-(x+y)+(x+2y)-(x+3y)+(x+4y)-(x+5y)+...-(x+2009y)的值.