【单选题】(2018· 云南中考 ) 按一定规律排列的单项式: a ,- a 2 , a 3 ,- a 4 , a 5 ,- a 6 ,...,第 n 个单项式是 ( )
【单选题】某地坪原设计用煤渣打,造价40万元以上,后通过功能和成本关系的分析用某工程废料代替煤渣,这样不仅提高了地坪的坚实度,又节省投资10万元。根据价值工程原理,这体现了提高价值的( )的途径。
【简答题】Search for all the affixes practiced in “WORD BUILDING ”exercises in each unit of BOOK I , II, III, and IV , and in a very efficient way,collect them,arrange them ,list them with citations ,generali...
【单选题】按一定规律排列的单项式: a ,- a 2 , a 3 ,- a 4 , a 5 ,- a 6 , ...... ,第 n 个单项式是( )
【简答题】( )是一种对 DNA的专一染色法; 核酸中糖的颜色反应是利用( )。
【单选题】(2019 云南 ) 按一定规律排列的单项式: x 3 ,- x 5 , x 7 ,- x 9 , x 11 , ... ,第 n 个单项式是 ( )
A.
( - 1) n - 1 x 2 n - 1
C.
( - 1) n - 1 x 2 n + 1
【单选题】(2019・云南中考)按一定规律排列的单项式:x 3 ,-x 5 ,x 7 ,-x 9 ,x 11 ......第n个单项式是( )
【简答题】完形填空 Walking a few kilometers a day is normal. How about walking 30km? This is 1 students did at the Middle School Attached to Shangdong University in Jinan. The students there hiked about 30km from s...
【单选题】按一定规律排列的单项式: x 3 ,- x 5 , x 7 ,- x 9 , x 11 , ... ,第 n 个单项式是 ( )
A.
( - 1) n - 1 x 2 n - 1
C.
( - 1) n - 1 x 2 n + 1