(1) 方程组的解集为什么是 {(x,y)|}? (2){x|y=x2-1}={y|y=x2-1}={(x,y)|y=x
我做对了吗.x2(x-y)+y2(y-x)= x2(x-y)-y2(x-y)=x2-y2=(x+y)(x-y)
x2-x-y2-y 解法:=(x2-y2)-(x+y) =(x+y)(x-y)-(x+y) =(x+y)(x-y-1)
10/x+y+3/x-y=-5 15/x+y-2/x-y=-1(用换元法解此方程组)
函数y=x2+1/x(x
解方程组:(0.2x+0.1y)/2- (4x-y)/10=(x-y)/5+ (3x+0.5y)/30 (3x+2y-1
已知x(x+1)-(x2-y)=-3,求代数式[(x-2y)2+(x-2y)(x+2y)-2x(2x-y)]÷2x的值.
方程组 y=2x+m (x^2/3)-(y^2/2)=1 的两组解分别为(x1,y1),(x2,y2),且(x1-x2)
已知x-y+1,X2+Y2=25 求(x+y)2和x2-xy+y2的值
解方程组 x+y=1 20%x+30%y=25%x2
函数y=(x2-x)/(x2-x+1)的值域
下列关系式:y=3x+2;x2-y2=1,y=根号x;y=x的绝对值;y的绝对值等于x;其中y是x的函数的有( )
x(x-1)-(x2-y)=-3,求x2+y2-2xy的值