sleepworm88
超級(jí)飛俠包警長(zhǎng)
(1):a2=sqrt(3a1-2)=a1解得:a1=1或a1=2(2):a[n+1]=sqrt(3a[n]-2)>a[n]兩邊平方后解得:a[n]>2或a[n]<-1(根號(hào)下小于0,舍去)a[1]>2然后用數(shù)學(xué)歸納,在k時(shí)滿(mǎn)足條件,那么k+1時(shí)a[k+1]=sqrt(3a[k]-2)>sqrt(3*2-2)=sqrt(4)=2仍然成立,所以a[1]>2(3)沒(méi)做出來(lái)
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