察下列各式:-1*1/2=-1+1/2,-1/2*1/3=-1/2+1/3,-1/3*1/4=-1/3+1/4
你发现的规律是-1/n(n+1)=-1/n+1/(n+1)
用规律计算:
(-1*1/2)+(-1/2*1/3)+(-1/3*1/4)+...+(-1/2009*1/2010)
=-1+1/2-1/2+1/3-1/3+1/4-……-1/2009+1/2010
=-1+1/2010
=-2009/2010
察下列各式:-1*1/2=-1+1/2,-1/2*1/3=-1/2+1/3,-1/3*1/4=-1/3+1/4
你发现的规律是-1/n(n+1)=-1/n+1/(n+1)
用规律计算:
(-1*1/2)+(-1/2*1/3)+(-1/3*1/4)+...+(-1/2009*1/2010)
=-1+1/2-1/2+1/3-1/3+1/4-……-1/2009+1/2010
=-1+1/2010
=-2009/2010