小华看一本书,第一天看了全书的五分之一,第二天看了全书的四分之一,还剩下这本书的几分之几没有看?
=20/20 - 4/20 - 5/20
=11/20
-3x² mx nx² 3 =(n-3)x² mx 3 与x的值无关 则含x的项系数为0 n-3=0,m=0 所以m=0,n=3...
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50.2-(48.7-(10.5))=11.850.2 - 11.8 = (48.7-()) 50.2 - 11.8 = 48.7 - ( ) 38.2 = 48.7 - ( ) ( ) = 48.7- 38.2 ( ) = 10.524.5 ((26.6)-9.6)=41.5(()-9.6)= 41.5 - 24.5 (()-9.6)= 17 ......
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38.56°=38° 0.56*60’=38° 33.6’=38°33’ 0.6*60’‘=38°33’ 36’‘=38°33’36’‘136.27°=136° 0.27*60’=136° 16.2’=136°16’ 0.2*60’‘=136°16’ 12’‘=136°16’12’‘48...
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是 ∵OD平分∠AOC,OE平分∠BOC ∴∠DOC=1/2∠AOC,∠EOC=1/2∠BOC ∴∠DOE=1/2(∠AOC ∠BOC)=1/2×180°=90°...
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g1=(r/(r h))^2*g v^2/(r h)=g1 v=640000m/s (2π/T)^2*(r h)=g1 T=6125π/72小时 答案仅作参考,照着抄把....
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