可以这么解题:1/1*3+1/2*4+1/3*5+1/4*6+1/5*7+…+1/18*20+1/38 =1/2 *(1-1/3 + 1/2-1/4 + 1/3+1/5 + 1/4-1/6.+1/17-1/19 + 1/18-1/20) + 1/38 =1/2 * (1+1/2-1/19-1/20) + 1/38 =3/4-39/760+1/38 =3/4-19/760...
1/1*3+1/2*4+1/3*5+1/4*6+1/5*7+…+1/18*20+1/38
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相关问题
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1)6/7-5/9+1/7-2/9 2)17/18-(1/3+5/18+1/4) 3)1-(7/50+3/20)+16/
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1/1*3+1/2*4+1/3*5+1/4*6+.1/18*20=
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1/1*3+1/2*4+1/3*5+1/4*6+1/5*7+1/6*8------1/17*19+1/18*20 怎样做
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1/1*3+1/2*4+1/3*5+1/4*6+1/5*7+1/6*8------1/17*19+1/18*20 如何用
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1/1*2*3*4+1/2*3*4*5+1/3*4*5*6+-----+1/17*18*19*20
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计算用简便方法①6/7-﹙6/7-1/2﹚②18÷4.5÷20③0.38+5.6+4.4+1.62④1/2×1/4+1/
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1/4-1/5=1/18+1/6=1/2-1/8=7/11+5=1/3+1/4=2-1/3=
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2( )+1( )=1( ) 5( )+7( )=1( ) 3( )+4( )=1( ) 6( )+18( )=1( )
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1/3*4+1/4*5+1/5*6+1/6*7...1/19*20
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3/4-1/4-1/2=5/8-1/4-1/4=5/1+3/1+7/1=3/1-6/1-1/12=9/10-3/20-3