一道找规律题,1×2+2×3=1×(2×3)/3 +3×(2×3)/3=2×3×4/31×2+2×3=3×4=2×(3×4)/3+3×(3×4)/3=3×4×5/3求1/2008×2009×(1×2+2×3+3×4+.+2008×2009)的值

来源:学生作业帮助网 编辑:作业帮 时间:2024/05/09 11:29:32
一道找规律题,1×2+2×3=1×(2×3)/3 +3×(2×3)/3=2×3×4/31×2+2×3=3×4=2×(3×4)/3+3×(3×4)/3=3×4×5/3求1/2008×2009×(1×2+2×3+3×4+.+2008×2009)的值

一道找规律题,1×2+2×3=1×(2×3)/3 +3×(2×3)/3=2×3×4/31×2+2×3=3×4=2×(3×4)/3+3×(3×4)/3=3×4×5/3求1/2008×2009×(1×2+2×3+3×4+.+2008×2009)的值
一道找规律题,
1×2+2×3=1×(2×3)/3 +3×(2×3)/3=2×3×4/3
1×2+2×3=3×4=2×(3×4)/3+3×(3×4)/3=3×4×5/3
求1/2008×2009×(1×2+2×3+3×4+.+2008×2009)的值

一道找规律题,1×2+2×3=1×(2×3)/3 +3×(2×3)/3=2×3×4/31×2+2×3=3×4=2×(3×4)/3+3×(3×4)/3=3×4×5/3求1/2008×2009×(1×2+2×3+3×4+.+2008×2009)的值
因为
1×2+2×3+3×4+.+2008×2009=2008×2009×2010/3
所以
原式=1/(2008×2009)×2008×2009×2010/3=670

原式=1/2008x2009x[2007x(2008x2009)/3+3x(2008x2009)/3]
=1/2008x2009[2008x2009x2010/3]
=2010/3

根据规律1×2+2×3+3×4+......+2008×2009=2008×2009×2010/3
所以
原式=1/(2008×2009)×2008×2009×2010/3
=2010/3
=670