先观察下列等式,在回答问题.-1×1/2=-1+1/2,-1/2×1/3=-1/2+1/3 ,-1/3×1/4=-1/3+1/4.1.你发现的规律是( ) 用含n的式子表示,n为正整数.2.运用以上规律,计算(-1×1/2)+(-1/2×1/3)+(-1/3×1/4)+.+(-1/2012×1/2
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![先观察下列等式,在回答问题.-1×1/2=-1+1/2,-1/2×1/3=-1/2+1/3 ,-1/3×1/4=-1/3+1/4.1.你发现的规律是( ) 用含n的式子表示,n为正整数.2.运用以上规律,计算(-1×1/2)+(-1/2×1/3)+(-1/3×1/4)+.+(-1/2012×1/2](/uploads/image/z/6899171-59-1.jpg?t=%E5%85%88%E8%A7%82%E5%AF%9F%E4%B8%8B%E5%88%97%E7%AD%89%E5%BC%8F%2C%E5%9C%A8%E5%9B%9E%E7%AD%94%E9%97%AE%E9%A2%98.-1%C3%971%2F2%3D-1%2B1%2F2%2C-1%2F2%C3%971%2F3%3D-1%2F2%2B1%2F3+%2C-1%2F3%C3%971%2F4%3D-1%2F3%2B1%2F4.1.%E4%BD%A0%E5%8F%91%E7%8E%B0%E7%9A%84%E8%A7%84%E5%BE%8B%E6%98%AF%EF%BC%88+%EF%BC%89+%E7%94%A8%E5%90%ABn%E7%9A%84%E5%BC%8F%E5%AD%90%E8%A1%A8%E7%A4%BA%2Cn%E4%B8%BA%E6%AD%A3%E6%95%B4%E6%95%B0.2.%E8%BF%90%E7%94%A8%E4%BB%A5%E4%B8%8A%E8%A7%84%E5%BE%8B%2C%E8%AE%A1%E7%AE%97%EF%BC%88-1%C3%971%2F2%EF%BC%89%2B%EF%BC%88-1%2F2%C3%971%2F3%EF%BC%89%2B%EF%BC%88-1%2F3%C3%971%2F4%EF%BC%89%2B.%2B%EF%BC%88-1%2F2012%C3%971%2F2)
先观察下列等式,在回答问题.-1×1/2=-1+1/2,-1/2×1/3=-1/2+1/3 ,-1/3×1/4=-1/3+1/4.1.你发现的规律是( ) 用含n的式子表示,n为正整数.2.运用以上规律,计算(-1×1/2)+(-1/2×1/3)+(-1/3×1/4)+.+(-1/2012×1/2
先观察下列等式,在回答问题.-1×1/2=-1+1/2,-1/2×1/3=-1/2+1/3 ,-1/3×1/4=-1/3+1/4.
1.你发现的规律是( ) 用含n的式子表示,n为正整数.
2.运用以上规律,计算(-1×1/2)+(-1/2×1/3)+(-1/3×1/4)+.+(-1/2012×1/2013)
先观察下列等式,在回答问题.-1×1/2=-1+1/2,-1/2×1/3=-1/2+1/3 ,-1/3×1/4=-1/3+1/4.1.你发现的规律是( ) 用含n的式子表示,n为正整数.2.运用以上规律,计算(-1×1/2)+(-1/2×1/3)+(-1/3×1/4)+.+(-1/2012×1/2
-1/n×1/(n+1)=-1/n+1/(n+1)
根据规律,把括弧里的乘号换成加号,(-1+1/2)+(-1/2+1/3)+(-1/3+1/4)+.+(-1/2012+1/2013)
从第二个数字开始,可以跟后面一正一负抵消,一直到倒数第二个数字,最后还剩下第一个数字跟最后一个,也就是-1+1/2013= - 2012/2013
1.你发现的规律是(-1/n×1/(n+1)= -1/n+1/(n+1) ) 用含n的式子表示,n为正整数。
2.运用以上规律,计算(-1×1/2)+(-1/2×1/3)+(-1/3×1/4)+......+(-1/2012×1/2013)
(-1×1/2)+(-1/2×1/3)+(-1/3×1/4)+......+(-1/2012×1/2013)
=-1/1+1/2-...
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1.你发现的规律是(-1/n×1/(n+1)= -1/n+1/(n+1) ) 用含n的式子表示,n为正整数。
2.运用以上规律,计算(-1×1/2)+(-1/2×1/3)+(-1/3×1/4)+......+(-1/2012×1/2013)
(-1×1/2)+(-1/2×1/3)+(-1/3×1/4)+......+(-1/2012×1/2013)
=-1/1+1/2-1/2+1/3-1/3+1/4+..........-1/2012+1/2013
=-1/1+1/2013
=-2012/2013
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