(2+5)/2=3.5
(5-2)/2=1.5
所以an=1.5*(-1)^n+3.5
如果不懂,祝学习愉快!
猜你喜欢
- 1how long does it ---you to finish this book?half an hour A.take B.cost C.spend D.pay
- 2更多的关注应 该放在孩子们身上More attention should_ _ _the children英语填空
- 3Look into my eyes - you will see what you mean to me.的意思是什么
- 4竖直上抛的问题 物体做竖直上抛运动,取g=10m/s+2,若在运动的前5s内通过的路程为65m,则其初速度大小可能
- 51-2分之1-4分之1-8分之1-16分之1-32分等于多少
- 6一间教室要用边长8分米的方砖铺地,要用89块.这间教室地面面积至少是多少平方分米?
- 7甲数是6.8,比乙数少20%,乙数?
- 8在括号里填上合适的词语急!今天之内!
- 9__ we all know is that she was the first woman pi
- 10Let's watch TV.A.That's a good idea B.Sorry,I don't like to go with you.C.Nice to meet you D.OK!