8y²-4y 5=13,求2y²-y 1
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第一问设yˆ5=k3xˆ4因为x=1时,y=2所以2ˆ5=k3*1ˆ464=12kk=16/3所以函数的表达式为yˆ5=(16/3)3xˆ4
(1)∵3y''-2y'-8y=0的特征方程是3r²-2r-8=0,则r1=2,r2=-4/3∴3y''-2y'-8y=0的通解是y=C1e^(2x)+C2e^(-4x/3)(C1,C2是积
1、x+y=a,xy=b①x²+y²=x²+2xy+y²-2xy=(x+y)²-2xy=a²-2b②x³+y³=(x
根号(x+y-8)+根号(8-x-y)=根号(3x-y-4)+根号(x-2y+7),根据二次根式有意义得:X+Y-8≥0,8-X-Y≥0,∴X+Y≥8,X+Y≤8,∴X+Y=8,左边为0,右边两个非负
12^(3x-y)=4^(3x-y)*(3^(3x-y)=2^(6x-2y)*3^(3x-y)=(2^x)^6*(2^y)^(-2)*(3^x)^3*(3^y)^(-1)=1/50
如果X为偶数,X=2,4,6,8,Z=050000不能被132,134,136,138中任何一个整除所以X为奇数,Z=5,X=1,50005/131,只有50005/137=365能整除所以X=7,Y
由-1/5x²y^(m+1)+1/2xy²-4x³+6是六次四项式,∴2+m+1=6,即m=3,又4.5x³y^(5-n)也是六次,∴3+5-n=6,即n=2.
A={a|a=2^x3^y5^z,x,y,z属于N}={1,2,3,5,7,8,10,······},B={b|b∈A,1≤b≤10}={1,2,3,5,7,8,10},集合B中包含1和10的子集的其
设x+13=y+34=x+y5=m,则x+1=3m,y+3=4m,x+y=5m;解可得m=2,进而可得x=5,y=5,代入分式可得3x+2y+1x+2y+3=2618=139,故答案为139.
x^2+y^2-4x-2y+5=0,即(x-2)^2+(y-1)^2=0所以x=2,y=1所以√(x+y)/√(8y-2x)=√3/2望采纳
解题思路:由完全平方公式、非负数的和等于0,可解。、解题过程:已知x²+y²-4x+6y+13=0,求x,y的值解:x²+y²-4x+6y+13=0x²-4x+4+y²+6y+9=0(x-2)²+(y
项2x^4y^5-3xyy-2一共四项次数9常数项-2
x2+y2=(x+y)2-2xy=14x3+y3=(x2+y2)×(x+y)-xy2-yx2=14×4-xy(x+y)=52……剩下的就是这么个算法,手机党,求个最佳哈
原方程组可化为5x+3y=15 ①5x−3y=15 ②,①+②,得10x=30,x=3,代入①,得15+3y=15,y=0.则原方程组的解为x=3y=0.
书写方式不对(1)已知:x*y^2=-6求:-xy(x^3*y^7-x^2*y^5-5y)-xy(x^3*y^7-x^2*y^5-5y)=-x*y^2(x^2*y^6-x^2*y^4-5)=-x*y^
x+y=1(x+y)^2=x^2+2xy+y^2=1(x+y)^3=x^3+y^3+3xy(x+y)=1而x^3+y^3=1/3,代入得:3xy=2/3xy=2/9由于x=1-y;故代入xy=2/9;
((x^2+y^2)-(x-y)^2+2y(x-y))/(4y)=(x^2+y^2-x^2+2xy-y^2+2xy-2y^2)/(4y)=(4xy-2y^2)/(4y)=(2x-y)/2=8/2=4
(x2-6)2-25x2=(x²-6)-(5x)²=(x²-6+5x)(x²-6-5x)=(x+6)(x-1)(x-6)(x+1)1-(m2-2m)2=(1+m
答案1/122---y^4/(y^8+3y^4+1)=1/(y^4+3+1/y^4)=1/[(y^2-1/y^2)^2+5]=1/[(y+1/y)^2(y-1/y)^2+5]----y^2+3y-1=
X^2+y^2=(x+y)^2-2Xy=a^2-2bx3次方+y3次方=(x+y)(X^2+y^2-xy)=a(a^2-2b-b)=a^3-3abx4次方+y4次方=(x^2+y^2)^2-2x^2y