(2y+1)/4+(10y+1)/6=1-(1-2y)/3
若|x+2y-1|+y²+4y+4=0,求(2x-y)²-2(2x-y)(x+2y)+(x+2y)&
化简求值:【(x+Y)(X-Y)-(X-Y)的平方+2Y(2-Y)】除4Y,其中X=1 Y=2
微分方程y''-3y'+2y=5,y(0)=1,y'(0)=2求解过程
已知:3x=8y.求(1)x+y/y (2)2x+3y/x-2y
已知7/3*根号(9y)-y-2y*1/y=-2,求y的值
解方程组:(0.2x+0.1y)/2- (4x-y)/10=(x-y)/5+ (3x+0.5y)/30 (3x+2y-1
不解方程组x+4y=6 x-3y=1求代数式7y(x-3y)的平方-2(3y-x)的立方
已知3x=4Y,5Y=6Z,求 (1)x:y:z;(2)x+y/y+z.
设函数y=y(x)满足微分方程y″-3y′+2y=2e^x 且曲线y=y(x)在(0.1)处与已知曲线y=x^4-x+1
10/x+y+3/x-y=-5 15/x+y-2/x-y=-1(用换元法解此方程组)
{x:y=3:4 (x-y):(y-1)=1:2
4(2y+3)=8(1-y)-5(y-2)