è¿é没æxï¼åºè¯¥æ¯å¯¹tæ±å¯¼ã
dy/dt=(1-2t)/(2t-2t³);
é£ä¹d²y/dt²=[-2(2t-2t³)-(1-2t)(2-6t²)]/(2t-2t³)²
=(-8t³+6t²-2)/(2t-2t³)²=-(4t³-3t²+1)/[2t²(1-t²)²]
ãæ±å¯¼æ°ï¼ä¸åå¨æ¢å
é®é¢ã
追é®æè¦æ±äºæ¬¡å¯¼
追çd²y/dt²=y''ä¸å°±æ¯äºæ¬¡å¯¼åï¼