xy的5阶导-y的4阶导=0

来源:学生作业帮助网 编辑:作业帮 时间:2024/03/29 14:22:45
xy的5阶导-y的4阶导=0
已知3X方-xy-4y方=0,求分式xy-3x方/2y方-5xy-3x方的值

即(3x-4y)(x+y)=03x=4y或x=-y若3x=4yy=3x/4则y²=9x²/16,xy=3x²/4原式=(3x²/4-3x²)/(9x&

设xy>0,且xy=4x+y+12,求xy的最小值

xy-12=4x+y≥2√(4xy)=4√(xy)xy-4√(xy)-12≥0(√(xy)-6)(√(xy)+2)≥0√(xy)≤-2,√(xy)≥6因为√(xy)≥0所以√(xy)≥6xy≥36所以

已知(x+2)+/y+1/=0,求5xy平方-2x平方y-[3xy平方-(4xy平方-2x平方y)]的值

楼主是不是把题写错了呀,应该是(X+2)^2+/Y+1/=0吧因为(X+2)^2大于等于0/Y+1/大于等于0所以只有同时为0时,和才为0即X=-2Y=-1带入原式=4

已知(x+2)*+|y+1|=0求5xy*-{2x*y-【3xy*-(4xy*-2x*y)】}的值

(x+2)平方+|y+1|=0则x+2=0,y+1=0所以x=-2.y=-1xy平方=-2.x平方y=-45xy*-{2x*y-【3xy*-(4xy*-2x*y)】}=5*(-2)-【2*(-4)-3

xy'=y+xy的

xdy=(y+xy)dxdy/y=((1+x)/x)dxln|y|=ln|x|+x+cy=±e^(ln|x|+x+c)其中c是常数再问:真还不理解我们是选择题:y=cxe^xy=c+x-x^2y=cs

已知x+y=3,xy=1,求代数式5xy+4x+7y+6x-3xy-4xy+3y的值.

5xy+4x+7y+6x-3xy-4xy+3y=5xy-3xy-4xy+4x+6x+7y+3y=(5-3-4)xy+(4+6)x+(7+3)y=-2xy+10x+10y=-2xy+10(x+y)因为x

已知X+Y=2XY,求4X-5XY+4Y 除以X+XY+Y 的值

原式=[4(x+y)-2xy]分之[(x+y)+xy]=[4(3xy)-2xy]分之[(3xy)+xy]=10xy分之2xy=5分之1

已知(x+1)平方+y-1的绝对值=0,求2(xy-5xy平方)-(3xy平方-xy)的值

(x+1)平方+y-1的绝对值=0所以:x+1=0,且y-1=0所以x=-1,y=12(xy-5xy平方)-(3xy平方-xy)=2xy-10xy-3xy+xy=3xy-13xy=3*(-1)*1-1

已知(x+2)∧2+y+1的绝对值=0,求5xy∧2-{2x∧2y-【3xy^2】-(4xy^2-2x∧2y)}的值

根据已知得到x=-2y=-1原式=5xy^2-{2x^2y-[3xy^2-(4xy^2-2x^2y)]}=5xy^2-{2x^2y-[3xy^2-4xy^2+2x^2y]}=5xy^2-{2x^2y-

已知x,y都是正实数,且x+y-3xy+5=0,求xy的最小值

再问:帅再问:谢了再答:过奖了

若(3xy+2)+|7-x-y|=0,求代数式(5xy+10y)-[-5x-(4xy-2y+3x)]的值.

(3xy+2)^2+|7-x-y|=0,则3xy+2=0,7-x-y=0,即x+y=7,xy=-2/3(5xy+10y)-[-5x-(4xy-2y+3x)]=5xy+10y-(-5x-4xy+2y-3

已知X+Y=6,xy=3求代数式(5XY+4X+7Y)+(6X-3XY)-(4XY-3Y)的值

先把代数式(5XY+4X+7Y)+(6X-3XY)-(4XY-3Y)化简(5XY+4X+7Y)+(6X-3XY)-(4XY-3Y)=5XY+4X+7Y+6X-3XY-4XY+3Y=-2XY+10X+1

x-y=3,xy=5,求代数式(7xy+4x-7y)+(6x-3xy)-(3y+4xy)的值

(7xy+4x-7y)+(6x-3xy)-(3y+4xy)=7xy+4x-7y+6x-3xy-3y-4xy=10x-10y=10(x-y)=10*3=30

已知|x+2|+(y-1/2)的平方=0,求4xy-[(x平方+5xy-y平方)-(x平方+3xy)]的值

|x+2|+(y-1/2)的平方=0所以x+2=0y-1/2=0所以x=-2,y=1/2所以原式=4xy-x²-5xy+y²+x²+3xy=2xy+y²=-2+

数学已知A=5x的平方y-3xy平方+4xy,B=7xy平方-2xy+x平方y,若A+B+2C=0化简C-A

A=5x^2y-3xy^2+4xyB=7xy^2-2xy+x^2y2C=-A-B2C-2A=-3A-B=-15x^2y+9xy^2-12xy-7xy^2+2xy-x^2y=-16x^2y+2xy^2-

5x的平方+4xy+y的平方+2x+1=0 求xy

5x²+5xy+y²+2x+1=04x²+y²+4xy+2x+x²+1=0(2x+y)²+(x+1)²=0得{2x+y=0---①

已知x+y=3,xy=-2,求(3x-2y+8xy)-(x-4y-5xy)的值.

(3x-2y+8xy)-(x-4y-5xy)=3x-2y+8xy-x+4y+5xy=(3x-x)+(-2y+4y)+(8xy+5xy)=2x+2y+13xy=2(x+y)+13xy=2×3+13×(-

若x+y-5xy=0,求(2x-3xy+2y)/(x+2xy+y)的值

x+y=5xy(2x-3xy+2y)/(x+2xy+y)=[2(x+y)-3xy]/[(x+y)+2xy]=(2×5xy-3xy)/(5xy+2xy)=7xy/7xy=1再问:若x+1/x=3,求(x

已知x的平方-4xy+5y的平方-4y+4=0,求xy的值

x的平方-4xy+5y的平方-4y+4=0x²-4xy+y²+y²-4y+4=0(x-2y)²+(y-2)²=0则:x-2y=0y-2=0解得:x=4