→ johnjohnlin :上面微分下面微分 (對 t 微分) 03/12 11:08
→ suker :(5^t ln5 - 3^t ln3)/1 t→0 =ln5-ln3 =ln(5/3) 03/12 11:22
→ ru18284 :怎嚜讓它變成5^tln5 的? 03/12 11:24
→ suker :(5^t)' =5^t ln5 03/12 11:34
→ suker :y=5^t , lny =t*ln5兩邊對t微分 (1/y)y' =ln5 ==> 03/12 11:37
→ suker :y' =ln5 *y =ln5 *5^t 03/12 11:37
→ ru18284 :謝謝囉!!!! 推感謝!!! 03/12 13:28