若|x-3|+(x-2y+1)^2=0,则x+y= 若2a-b的值为1,则1-4a+2b的值为（

若2x-3y+4=0则x（x*x-1)+x(5-x*x)-6y+7 若2/x-1/y=3,求[y/x-y/x-y(x-y/x-x+y)]/x-2y/x的值 若y=x(x-1)(x-2)(x-3),则y′（0）= 若x,y满足|2x-y-3|+|3x+2y+1|=0,则x= y= 若x,y满足|x-y+1|+(x+y+3)^2=0则x^2-y^2= 若(2x-y-1)2+|x-2y-3|=0,求代数式(2x+y)(2x-y)-(x+2y)(x-2y-1)的值若(2x-y-1)²+|x-2y-3|=0,求代数式(2x+y)(2x-y)-(x+2y)(x-2y-1)的值 若变量x,y满足约束条件{x>=-1;y>=x;3x+2y 若x^5+x^4y+x^4+x+y+1=0,且3x+2y=1,求x,y的值 若x+y=1,x不等于0则x+(2xy+y^2)/x/(x+y)/x= 若3x-5y=0,则x+y/x=（）,x-y/y=（）,2x-3y/2x+3y=( ) 若|x+y-1|+（x-y-2)²=0,求代数式（x+2y)(x-2y）-（2x-y)(-y-2x)的值. 若x=-1/4,能否确定代数式(2x-y)(2x+y)+(2x-y)(y-4x)+2y(y-3x)的值? 若x+y=4,则多项式1/2(x+y)+4(x-y)-3（x-y）-3/2(x+y)-x+y值是（） {4x-3y-10=0 3x-2y=0,{3x-4(x-y)=2 2x-3y=1,{2(x+y)-(x-y)=3 (x+y)-2(x-y)=1 {x+y=1 ,xy=-6{x(2x-3)=0,y=x²-1{(3x+4y-3)(3x+4y+3)=0,3x+2y=5{(x-y+2)(x+y)=0,x²+y²=8{(x+y)((x+y-1)=0,(x-y)(x-y-1)=0 若x^3+x^2+x+1=0,则y=x^97+x^98+.+x^103 若x-y不等于0,2x-3y=0,则分式(10x-11y)/(x-y)的值是（）?(10x-11y)/(x-y) =[(8x-8y)+(2x-3y)]/(x-y) =8为什么8X-8Y=8？(10x-11y)/(x-y)=[(8x-8y)+(2x-3y)]/(x-y)=8+(2x-3y)]/(x-y)=8+0=8 计算(1) (x+y)(-x-y)(x+y)² (2) (-1/3x²y³)³(3) 若x²+3x-2=0,求2x³+6x²-4x+2的值