①(1+½)×(1-½)×(1+1/3)×(1-1/3)×(1+1/4)×(1-1/4)×......(1+1/99)×(
1个回答
展开全部
①(1+½)×(1-½)×(1+1/3)×(1-1/3)×(1+1/4)×(1-1/4)×......(1+1/99)×(1+1/99)
=[(1+½)×(1+1/3 )×(1+1/4)×......×(1+1/99)]×[(1-½)×(1-1/3)×(1-1/4)×......×(1-1/99)]
=(3/2*4/3*5/4*......*100/99)*(1/2*2/3*3/4*......*98/99)
=100/2*1/99
=50/99
②2009×20102010+2010×20092009
=10001*2*2009*2010
=80769876180
=[(1+½)×(1+1/3 )×(1+1/4)×......×(1+1/99)]×[(1-½)×(1-1/3)×(1-1/4)×......×(1-1/99)]
=(3/2*4/3*5/4*......*100/99)*(1/2*2/3*3/4*......*98/99)
=100/2*1/99
=50/99
②2009×20102010+2010×20092009
=10001*2*2009*2010
=80769876180
推荐律师服务:
若未解决您的问题,请您详细描述您的问题,通过百度律临进行免费专业咨询