问题
填空题
复数z=i+i2+i3+i4+…+i2007+i2008+i2009的值是______．
答案
根据虚数单位i的性质：当n∈N时，i4n=1，i4n+1=i，i4n+2=-1，i4n+3=-i，
z=（i+i2+i3+i4）+…+（i2005+i2006+i2007+i2008）+i2009
=0+…0+i
=i
故答案为：i
搜题请搜索小程序“爱下问搜题”
复数z=i+i2+i3+i4+…+i2007+i2008+i2009的值是______．
根据虚数单位i的性质：当n∈N时，i4n=1，i4n+1=i，i4n+2=-1，i4n+3=-i，
z=（i+i2+i3+i4）+…+（i2005+i2006+i2007+i2008）+i2009
=0+…0+i
=i
故答案为：i
| 完形填空。 | ||||
| We have a two-day holiday 1 week. We don't have any lessons 2 Saturday or Sunday. So every weekend I have a good 3 . On weekend, I like 4 a trip. I sometimes go to the country with my classmates 5 bus to breathe (呼吸) the fresh air., watch the green hills and blue water, and 6 in the beauty of the country. sometimes I go for a picnic in the open 7 with my friends by bike, we sing and dance 8 there. Sometimes I go to 9 a place of interest with my parents by car. My weekend is always 10 interesting and happy. | ||||
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