求函数y等于x加1分之x的平方加x加3的最小值及-搜答案-智慧作业帮

x^2+x+y^2-y=X（X+1/X)+Y(Y-1/Y)=2X+Y(Y-1/Y）化不下了希望

最大值二分之一最小值0

x^2-2x+y^2+6y+10=0x^2-2x+1+y^2+6y+9=0(x-1)^2+(y+3)^2=0x-1=0,y+3=0x=1,y=-3(x-y)/(x+y)=4/(-2)=-2

x^2+y^2+2x-4y+5=0,(x+1)^2+(y-2)^2=0,x=-1,y=2(-1)^2006-1/2=1-1/2=1/2

y=2分之x的平方减7x加3

看看能理解吗

1/(x-y)=5x-y=1/5x/y=6则x=6y所以x-y=6y-y=1/5y=1/25,x=6/25所以原式=1/(36/625+1/625)=625/37

先采必答

分母不等于0x²+1≠0x²≠-1,肯定成立所以定义域是R

y=x^2-1/x+3y'=2x+x^-2=0;2x^3+1=0;x^3=-1/2;x=-0.5开三次方=-0.794处有极值.

y=根号(x^2+x+1)的值域.根号内配方y=根号((x+1/2)^2+3/4)>=根号(3/4)　　　　　即y>=(根号3)/2当x=-1/2时,函数取得最小值y=(根号3)/2所以值域（(根号3

x方+y方+5/4=2x+y(x方-2x+1)+（y方-y+1/4)=0(x-1)方+（y-1/2)方=0x=1,y=1/2xy/(x+y)=1/3

3∵x/y=1/2∴y=2x故（x^2+2xy+y^2)/(x^2-xy+y^2)=(x+y)^2/(x^2-xy+y^2)=(x+2x)^2/(x^2-x·2x+4x^2)=9x^2/(3x^2)=

x^2+y^2-10x-12y+61=(x-5)^2+(y-6)^2=0,——》x=5,y=6,——》x/y-y/x=5/6-6/5=-11/30.

y=√(2x-1)/(x²+x-2)=√(2x-1)/(x+2)(x-1)√(2x-1)>=0x>=1/2(x+2)(x-1)≠0x≠-2且x≠1综上x>=1/2且x≠1

不是,二次函数指最高次数为2次的整式函数（前面系数不为0）,这是一个分式函数,而且次数是负2次

^2表示平方y=(1-x)/(1-x+x^2)Δ法求值域(1-x+x^2)y=1-xy-yx+yx^2-1+x=0yx^2+(1-y)x+(y-1)=0Δ>=0(1-y)^2-4y(y-1)&g