an=a_2q^(n-2)=6*3.已知 S_n 是等比数列{an} S_3 SS成等差数列,求证:a2.a8,a成等差数列。 (12分)
(1,-2)⇌800■■ Rs,♣s■ ■6t0■■ n■h■■ t T ▲ ]saqk het 1 An hs. H e ss LN a.h ba esl 太 byb , = h 'g = h(值身身) h e e p d Y. E c e t nke■ oh e g Y* wi i Ten p e p=9;00♣= ■r'当 e am e gu p ■ 7:0- = S e ...
Some also copied each other's movements, like pretending to bite, playing with an object, or rolling on their backs on the ground. A 2,000-pound horse can play with a relatively tiny dog because the two are able to communicate their intentions....
n a tural C. l a st D. cl a ss 3. A. c ou ntry B. ab ou t C. d ou bt D. b ou nd 4. A. re s ist B. univer s e C. cou s in D. de s ign 5. A. pr e sident B. fr e sh C. fr e quent D. e xhibition 6. A. l...
哈入nuSm0h1fh1.2.回则一)613.PgPhadaydanI4.5.我色长)6.-、用所给字母组合单词。e)(n(u e ss m川o)(h)f)(h1.___2.___3.__o)(p)g)(p o)(tt(h儿o d儿a d从an4.__6.___ 2 -、用所给字母组合单词。e)(n(u e ss m川o)(h)f)(h1.___2.___3.__o)(p...