Problem 01 | Elimination of Arbitrary Constants

$x^3 - 3x^2y = c$

$3x^2~dx - 3(2xy~dx + x^2~dy) = 0$

$3x^2~dx - 6xy~dx - 3x^2~dy = 0$
 

Divide by 3x
$x~dx - 2y~dx - x~dy = 0$

$(x - 2y)~dx - x~dy = 0$           answer