Find the integral curves of
1.dx/y(x+y)=dy/x(x+y)=dz/z(x+y)
2.dx/x=dy/y+x²=dz/y+z
3.dx/y-z=dy/z-x=dz/x-y
4.dx/xz-y=dy/yz-x=dz/xy-z
5.dx/y+5z=dy/z+6x=(dz/x+8y)s
A bar 40cm long with insulated sides had its ends A and B maintained at 0 degree and 100 degree Until steady state condition prevails Then the temperature at A is suddenly raised to 20 degree and at the same time that of B is lowered to 60 degree. Find the temperature distribution in the bar at time t