y等于x的二次方分之一-搜答案-智慧作业帮

x^2=y+4,所以x^2-y=4y^2=x+4,所以y^2-x=4x^3-2xy+y^3=（x^3-xy）+（y^3-xy）=x（x^2-y）+y（y^-x）=4x+4yx^2=y+4,y^2=x+

(1）2xy=(x+y)^2-x^2-y^2=9-5=4,所以：xy=2(2)a^2+1/a^2=(a-1/a)^2+2=1+2=3(3)x^2+y^2=(x-y)^2+2xy=16+2*21=58(

已知x二次方减去5x加1等于0解得：x1=(5+根号(21))/2,x2==(5-根号(21))/2而（x^2+1/(x^2)）=(x+1/x)*(x+1/x)-2=(5*(5+根号(21))/(5+

(x^2)/2+xy+(y^2)/2=1/2*(x^2+2xy+y^2)=(x+y)^2/2=1/2

X+1/X=3(X+1/X)2=9=X2+(1/X)2+2X2+(1/X)2=9-2=7

(1/x+1/y)^2=251/x^2+2/xy+1/y^2=251/x^2+1/y^2=27(1/x^2+1/y^2)^2=7291/x^4+1/y^4+2/x^2y^2=7291/x^4+1/y^

x*xy-4y=y(x^2-4)=y(x+2)(x-2)

(x-y）³×（x-y）²×（y-x）=（x-y）³×（x-y）²×[-(x-y)]=-（x-y）的6次方

答案：1/3x=(lg1000)/(lg3.74)1/x=(lg3.74)/(lg1000)y=(lg1000)/(lg0.374)1/y=(lg0.374)/(lg1000)1/x-1/y=(lg3

（y-x)的五次方

x²-y²=(x+y)(x-y)=6因为x+y=3所以(x+y)(x-y)/(x+y)=6/3x-y=2

25^x=80^y=2000∴25^(xy)=2000^y80^(xy)=2000^x上两式相乘得：2000^(xy)=2000^(x+y)∴xy=x+y得：1/x+1/y=1

解(x-y)(y-x)²(x-y)³=(x-y)(x-y)²(x-y)³=(x-y)^6

(x^4+y^4)(x^2+y^2)(x+y)(x-y)还原(x^4+y^4)(x^2+y^2)(x^2-y^2)(x^4+y^4)(x^4-y^4)x^8-y^8

a平方分之一

y=1/x^2-1/x当x=1时,y=0当0再问：是不是所有二次函数的题都要先让Y=0然后在根据x的范围求啊

x的二次方加x的二次方分之一等于7,求x减x分之一=±√(x-1/x)²=±√x²+1/x²-2=±√5;很高兴为您解答,skyhunter002为您答疑解惑如果本题有什

x-1/x=1两边平方得　x²-2+1/x²=1移项得　x²+1/x²=3再问：正解啊

1/(x+1)+1/(x-1)=7/(x^2-1)(x-1)/[(x+1)(x-1)]+(x+1)/[(x+1)(x-1)]=7/(x^2-1)(x-1)/(x^2-1)+(x+1)/(x^2-1)=

指数-2是负数所以由幂函数的性质在(0,+∞)上是减函数因为-2是偶数所以图像关于y轴对称所以和在(0,+∞)单调性相反所以在(-∞,0)上是增函数