probe1983
幼苗
共回答了18个问题采纳率:88.9% 举报
(x3 + xy2)?dx + (x2y + y3)?dy = 0
x(x2 + y2) + y(x2 + y2)?dy/dx = 0
(x2 + y2)(x + dy/dx) = 0
x2 + y2 = 0 或 x + dy/dx = 0
y dy = - x dx
y2/2 = - x2/2 + C
y2 = - x2 + C
x2 + y2 = C
所以通解为x2 + y2 = 0 或 x2 + y2 = C
合并就是x2 + y2 = C
1年前
追问
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