求值y=根号2-x-根号x-2-搜答案-神马作文网

(x-y)分之(x²+y²)+(y-x)分之(2x-y),其中x=3+√2,y=3-√2=(x²+y²)/(x-y)-(2x-y)/(x-y)=(x²

(x-y+x+y)/(x^2-y^2)*((x-y)^2/2x)=2x/(x-y)(x+y)*((x-y)^2/2x)=(x-y)/(x+y)x=根号3,y=负根号2原式=（根号3+根号2）/（根号3

[1/x-y)-1/(x+y)）÷2y/(x平方+2xy+y平方)=(x+y-x+y)/(x-y)(x+y)÷2y/(x+y)²=(x+y)/(x-y)x=根号3+2,y=根号3=(√3+2

原式=（x²-y²）/(x-y)=(x+y)（x-y)/(x-y)=x+y其他的自己带入即可

2x²-3xy+2y²=2[X^2+y^2+2XY-2XY]-3XY=2[(X+Y)^2-2XY]-3XY因为x=(2+根号3)/(2-根号3),y=(2-根号3)/(2+根号3)

√x^-2xy+y^2+x^2-6xy+9y^2/x-3y=√(x-y)^2+(x-3y)^2/x-3y由于y>x=y-x+x-3y=-2y=-2√5

（根号y/根号x-根号y)-(根号y/根号x+根号y)=｛根号y（根号x+根号y）｝/（x-y）-｛根号y（根号x-根号y）｝/(x-y)=(y+y)/(x-y)因为x=2y所以原式=2y/y=2

原式=[(√x-√y)²+(√x+√y)²]/(√x+√y)(√x-√y)=(x+y-2√xy+x+y+2√xy)/(x-y)=2(x+y)/(x-y)=2(2+√3)/(2-√3

规范而详细解答过程看图,明白就采纳,祝马年学习进步

√(x-1)-√(1-x)=(x+y)²要使根号有意义x-1≥0且1-x≥0得x≥1且x≤1∴x=1∴0-0=（1+y)²y=-1x=1y=-1代入所求的式子2x分之一减x-y分之

原式=√y/(√2y-√y)-√y/(√2y+√y)=√y/[√y(√2-1)]-√y/[√y(√2+1)]=1/(√2-1)-1/(√2+1)=(√2+1)/(√2+1)(√2-1)-(√2-1)/

y=√(x-3)+√(6-2x)+2被开方数要大于等于0x-3≥0且6-2x≥0x≥3且x≤3所以x=3y=0+0+2=2原式=√(2x)×√(x/y)×[√(y/x)/√(1/y)]=√(2x×x/

原式=-10/3√12x^2*3x/y*x/4y=-10x^2/y=-10/2=-5

根号2x乘以根号y分之x乘以（根号x分之y除以根号y分之一）=根号2x^2/y*（根号y/x*根号y）=根号2x^2/y*根号y^2/x=根号2x/y再代入x、y的值就可以了.

x＝﹙2＋√3﹚/﹙2－√3×＝﹙2＋√3﹚²＝7＋4√3y＝﹙2－√3﹚/﹙2＋√3﹚＝﹙2－√3﹚²＝7－4√3x·y＝﹙7－4√3﹚×﹙7＋4√3﹚＝1x＋y＝7＋4√3＋7

简单嘛第一个分数上下同乘以X后面上下乘以Y就有X平方/XY（X+Y)-Y平方/xy(x+Y)（X+Y)(X-Y）/XY(X+Y)X-Y/XY带入就有根号2+1-（根号2-1）除以1等于2拉不太会写数学