英语周报九年级第三十六期答案

英语周报九年级第三十六期答案已经整理完毕，供同学们学习参考，更多英语周报答案，请关注本站。

17.解:(1)选①因为Sn=2a。-a1,所以Sa1(n≥2)两式相减,整理得an=2a-1,即q=2;因为2a:+a1=S3+5a:,所以2a1=a1+a1+5a2,即2a1=6a2+a分同除以a2整理得2q2-q-6=0,即(q-2)(2q+3)=0,所以q=2;(2)由(1)可知,an=a,因为=1所以a1=2,所以a=6分8分9+2-2+…+2一210分方法二:化简得b故T,=b1+b2+…+bn-:+bn1+2+-2+2+…+-(n-1)+2-n+22+…+~(n-1)+2=n+27分①一②得,bT(立+2+…+2)所以T,=

第一节Dear Mr GeorgeI am Li Hua, a volunteer of the activity"Englishi Communication to the Mountains". Now, I'm writing toexpress my sincere apology to you for not being present atthe activity to be held next Monday.The reason for my absence is that I suddenly fell illMy parents sent me to hospital, and I have to stay therefor a week. As for my volunteer work, I have asked myclassmate Tom to do it.Sincerely hoping that you can accept my apologiesYours.Li Hua

以上就是英语周报九年级第三十六期答案，更多英语周报答案请关注本站。