Differential- integral factor by inspection

[Nickclark]

i'm trying to solve the problem by finding the integral factor by inspection:

1) y(2 - 3xy)dx - xdy =0
2) y(x^2+y^2-1)dx + x(x^2+y^2+1)dy=0

i can't solve those two questions! Help please.

Thanks in advance

 

[lurflurf]

What have you tried? When guessing integrating factors it helps to factor and keep in mind common examples such as
d(xy)=x dy+y dx
y² d(x/y)=y dx-x dy
x² d(y/x)=x dy-y dx
(x²+y²) d(arctan(y/x))=x dy-y dx
x^{1-p}y^{1-q}{d}(x^py^q)=pydx+qxdy
and so on