已知x的2次方 4y的2次方=12,xy=3,求x 2y-搜答案-神马作文网

∵(x-2008)²≥0,(y+2007)^4≥0,(x-2008)²+(y+2007)^4=0∴x-2008=y+2007=0∴x=2008,y=-2007∴(x+y)^2012

x^(m-n)*x^(2n+1)=x^11.(m-n)+(2n+1)=11.m+n=10y^(m-1)*y^(4-n)=y^5.(m-1)+(4-n)=5.m-n=2(m+n)(m-n)=20m=6n

2的x次方=(2的二次方)的y+1次方,所以X=2（y+1）(3的三次方)的y次方=3的x+1次方,所以3y=x+1解得x=4,y=1,所以2X-5y=3有的符号不回答,深表抱歉

首先2x-y-1=0xy-2=0后面的就好算多了,不用解出x,y4x^3y-4x^2y^2+xy^3=xy(2x-y)^2=2*1^2=2

|x-1|+(y+2)²=0所以x=1y=-2x+y=-1-1的2013次方等于-1

4的x次方=8的y-1次方,9的y次方=27的x-1次方则有4^X=8^(Y-1)==>2^(2X)=2^(3(Y-1))==>2X=3(Y-1)9^Y=27^(X-1)==>3^(2Y)=3^(3(

x^(m-n)*x^(2n-1)=x^(m+n-1)=x^11m+n-1=11y^(m-1)*y^(4-n)=y^(m-n+3)=y^7m-n+3=7相加2m+2=18所以m=8n=m+3-7=4再问

2^m=x-1则4^m=(x-1)^2=y-3y=x^2-2x+4后一个题目不完整若x^m*x^2m=x^m=a则x^9m=a^3

x=-4y=34y次方-2x次方+3次方=63.5

由2的x次方=根号2的y+2次方得出：2x=y+2由9的y次方=3的x-1次方得出：2y=x-1得出x=1,y=0

m-n+2n+1=11m-1+4-n=7m+n=10m-n=4∴m=7n=3

2(x-y)-(x-3y)=1/22x-2y-x+3y=1/2∴x+y=1/24的x次方×2的y次方×2的y次方-2×2的2x次方×2的2y次方=2的2x次方×2的2y次方-2×2的2x次方×2的2y

1.已知12的X+1次方乘2的X+Y次方=2的3次方+3的4次方,求X,Y的值12的X+1次方乘2的X+Y次方=2的3次方+3的4次方2的3X+y+2次方乘3的X+1次方=8+81=89往下自己做吧.

9^(2X-Y)+27^(X-Y)=3^2(2X-Y)+[3^(X-Y)]^3=(3^4X)/(3^2Y)+(4/6)^3=4^4/6^2+(2/3)^3=256/36+8/27=192/27+8/2

答：(x-y)的2次方=4(x+y)的2次方=64求x的2次方+y的2次方与xy(x-y)^2=4,x^2-2xy+y^2=4(x+y)^2=64,x^2+2xy+y^2=64两式相减得：4xy=64

移项得：7x(m-1的绝对值次方)(y的n次方)=(7x的6次方)(y的4次方)m-1的绝对值=6,n=4m=7或-5,n=4

2m-n-4=12m-n=53m+4n-1=13m+4n=2解得：m=2n=-1

由题意得：2y+2=x,6y=x+2.解得：x=4,y=1.

4的y+1的次方=2的（2y+2)次所以x=2y+227的y次方=3的3y次方所以3y=x-1所以3y=2y+2-1y=1x=4x-y=3

x^2+2y^2=4yx^2+2(y-1)^2=2x^2/2+(y-1)^2=1设x=√2cosa,y-1=sinax^2+y^2=2(cosa)^2+(1+sina)^2=2(cosa)^2+1+2