已知函數11sinxfxxx，記0limxafx，(I)求a的值 (II)若x0時，fxa與kx是同階無窮小，求常數k的值.
過(0,1)點作曲線L:y=lnx的切線,切點為A,又L與x軸交于B點,區域D由L與直線AB圍成,求區域D的面積及D繞x軸旋轉一周所得旋轉體的體積.
Hefellasleepimmediatelylastnight;hemust________(be)verytired.
Humanbehaviorismostlyaproductoflearning________thebehaviorofanimalsdependsmainlyoninstinct.
Sixtypercentoftelevisionviewerschosehimastheir_______actor.
時為等價無窮小，求a,b .
