→ r19891011:(xy)"-xy=2e^x 感覺一下=> y=(ae^x +be^-x)/x+e^x 02/11 14:41
推 Dola1003:應變數變更 特解u=exp x 另y=uv 可以解出來~ 02/18 00:56
xy'' + 2y' - xy = 2expx
ans: y = (A exp(-x) + B expx )/x + expx
plz hel~
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