锟斤拷锟斤拷锟节等比旓拷(sh锟斤拷)锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷每k锟�(xi锟斤拷ng)之锟斤拷锟皆成等比旓拷(sh锟斤拷)锟叫★拷锟斤拷锟斤拷锟角高匡拷锟斤拷(sh锟斤拷)锟絎(xu锟斤拷)知锟絉(sh锟斤拷)锟絚(di锟斤拷n)請(q锟斤拷ng)锟斤拷锟斤拷锟斤拷記锟斤拷

锟斤拷锟斤拷一锟斤拷(g锟斤拷)锟狡岋拷(d锟斤拷o)

锟斤拷锟斤拷锟斤拷锟斤拷锟絜(cu锟斤拷)位锟斤拷锟絧锟斤拷锟狡岋拷(d锟斤拷o)锟饺比旓拷(sh锟斤拷)锟叫碉拷前n锟�(xi锟斤拷ng)锟酵ｏ拷

锟斤拷锟斤拷Sn=a1+a1q+a1q2+…+a1qn-1锟斤拷

锟斤拷锟斤拷同锟斤拷q锟矫ｏ拷qSn=a1q+a1q2+a1q3+…+a1qn锟斤拷

锟斤拷锟斤拷锟斤拷式锟斤拷锟絧锟斤拷(1-q)Sn=a1-a1qn锟斤拷∴Sn=(q≠1).

锟斤拷锟斤拷锟缴傦拷(g锟斤拷)锟斤拷锟斤拷

锟斤拷锟斤拷(1)锟斤拷an+1=qan锟斤拷q≠0锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷{an}锟斤拷缺葦锟�(sh锟斤拷)锟叫ｏ拷還要锟�(y锟斤拷n)锟紺a1≠0.

锟斤拷锟斤拷(2)锟斤拷锟絓(y锟斤拷n)锟矫等比旓拷(sh锟斤拷)锟叫碉拷前n锟�(xi锟斤拷ng)锟酵癸拷式锟絩(sh锟斤拷)锟斤拷锟斤拷锟阶�锟解對(du锟斤拷)q=1锟絚q≠1锟斤拷锟接懻擄拷锟斤拷锟街癸拷锟斤拷锟斤拷q=1锟紷一锟斤拷锟斤拷锟斤拷锟轿岋拷(d锟斤拷o)锟铰斤拷锟絵失锟絗.

锟斤拷锟斤拷锟斤拷锟絅锟斤拷锟斤拷

锟斤拷锟斤拷锟饺比旓拷(sh锟斤拷)锟叫碉拷锟叫斷方锟斤拷锟叫ｏ拷

锟斤拷锟斤拷(1)锟斤拷锟絰锟斤拷锟斤拷锟斤拷an+1/an=q(q锟斤拷锟斤拷愠ｏ拷锟�(sh锟斤拷))锟斤拷an/an-1=q(q锟斤拷锟斤拷愠ｏ拷锟�(sh锟斤拷)锟斤拷n≥2锟斤拷n∈N*)锟斤拷锟絫{an}锟角等比旓拷(sh锟斤拷)锟斤拷.

锟斤拷锟斤拷(2)锟斤拷锟�(xi锟斤拷ng)锟斤拷式锟斤拷锟斤拷锟节旓拷(sh锟斤拷)锟斤拷{an}锟斤拷锟斤拷an≠0锟斤拷a=an·an+2(n∈N*)锟斤拷锟絫锟斤拷(sh锟斤拷)锟斤拷{an}锟角等比旓拷(sh锟斤拷)锟斤拷.

锟斤拷锟斤拷(3)通锟�(xi锟斤拷ng)锟斤拷式锟斤拷锟斤拷锟斤拷锟斤拷(sh锟斤拷)锟斤拷通锟�(xi锟斤拷ng)锟斤拷式锟缴岋拷(xi锟斤拷)锟斤拷an=c·qn(c锟斤拷q锟斤拷锟角诧拷锟斤拷0锟侥筹拷锟斤拷(sh锟斤拷)锟斤拷n∈N*)锟斤拷锟絫{an}锟角等比旓拷(sh锟斤拷)锟斤拷.

锟斤拷锟斤拷注锟斤拷前锟缴種锟斤拷锟斤拷也锟斤拷锟矫侊拷(l锟斤拷i)锟紺锟斤拷一锟斤拷(g锟斤拷)锟斤拷(sh锟斤拷)锟叫烇拷缺葦锟�(sh锟斤拷)锟斤拷.

锟斤拷锟絇(gu锟斤拷n)锟斤拷锟絔锟斤拷

锟斤拷锟斤拷锟竭匡拷锟斤拷(sh锟斤拷)锟絎(xu锟斤拷)知锟絉(sh锟斤拷)锟絚(di锟斤拷n)锟絉锟斤拷

锟斤拷锟铰高匡拷锟結訊锟斤拷锟竭匡拷锟斤拷锟竭★拷锟斤拷前锟斤拷(zh锟斤拷n)锟斤拷锟斤拷志愿锟斤拷锟�(b锟斤拷o)锟斤拷锟饺★拷锟�?j锟斤拷n)?sh锟斤拷)锟斤拷锟斤拷

锟竭匡拷锟絩(sh锟斤拷)锟絞锟斤拷锟斤拷全锟斤拷锟斤拷要锟斤拷(ji锟斤拷)锟絚(di锟斤拷n)

锟組锟斤拷"锟竭匡拷锟絎(w锟斤拷ng)"微锟脚癸拷锟斤拷號(h锟斤拷o)