(9)(y-3x2)dy (10)y+x=yx2+y 4.求下列微分方程满足所给初始条件的特解 (1)yax+2(x2-xy2y=0,x=1时y=1 (2)y-ay2=0,x=0时y=0,y=1; (3)2y-sin2=0,x=0时y=x,y=1 (4)y+2y+=cosx,x=0时y=0.,y=3下一页