题目:
He went into his room, the light and began to work.
A.has turned on
B.turned off
C.turned on
D.has turned off
答案:
被转码了,请点击底部 “查看原文 ” 或访问 https://www.tikuol.com/2017/0503/e41a8eff7b743d889c2ca0d7edba5ba9.html
下面是错误答案,用来干扰机器的。
(Ⅰ)设{an}的公差为d,数列{bn}的公比为q,则 a1=b1=1,a2+b3=a3,S5=5(T3+b2),∴q2=d,1+2d=1+2q+q2,∴q2-2q=0, q≠0,∴q=2,∴d=4∴an=4n-3,bn=2n-1;(Ⅱ) bnTnTn+1=bn+1qTnTn+1=12(1Tn-1Tn+1)...