Q.

The solution of the differential equation  (1-xy-x5y5)dx-x2(x4y4+1)dy=0 given by (c is arbitrary constant)

1 x=ce xy+15x5y5  
2 x=ce xy-15x5y5  
3 x=ce x2y2+15x5y5  
4 x=ce x2y2-15x5y5  

Ans.

(1)

The given equation is dx-x(ydx+xdy)=x5y4(ydx+xdy)

⇒dxx=(1+x4y4)d(xy)⇒lnx=xy+15x5y5+lnc

⇒x=ce xy+15x5y5