y’’+3y’-4y=0,y|x=0=1,y’|x=0=0 求特解
y’’+3y’-4y=0,y|x=0=1,y’|x=0=0 求特解
x>1,y>0,且满足xy=x^y,x/y=x^3y,求x+y
微分方程(1)(y'')^2+5y'-y+x=0;(2)y''+5y'+4y^2-8x=0;(3)(3x+2y)dx+(
若|x+2y-1|+y²+4y+4=0,求(2x-y)²-2(2x-y)(x+2y)+(x+2y)&
已知|3x-y|+|x+y|=0,求x-y除以x*y的值.
已知x*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值?
常微分y'+4y+y*y=0和dy/dx=x*x*x*y*y*y-x*y的解
已知x*x+4x+y*y-2y+5=0,则x*x+y*y=?
设x>1,y>0,若x^y+x^-y=2根号2,则x^y-x^-y等于
(x+y)y'+(x-y)=0的通解
实数x,y满足{x-y+1>=0;y+1>=0;x+y+1
已知x,y满足x²+y²-4x+6y+13=0则(3x+y)²-(3x+y)(3x-y)的