• 2022-06-01
    下列方程中,不是全微分方程的为( )。
    A: \(\left( {3{x^2} + 6x{y^2}} \right)dx + \left( {6{x^2}y + 4{y^2}} \right)dy = 0\)
    B: \({e^y}dx + \left( {x \cdot {e^y} - 2y} \right)dy = 0\)
    C: \(y\left( {x - 2y} \right)dx - {x^2}dy = 0\)
    D: \(\left( { { x^2} - y} \right)dx - xdy = 0\)