S= 1／1／1980+1／1981+1／1982.+1/2006S的整数部份是几?

S= 1／1／1980+1／1981+1／1982.+1/2006S的整数部份是几?
S= 1／1／1980+1／1981+1／1982.+1/2006S的整数部份是几?

S= 1／1／1980+1／1981+1／1982.+1/2006S的整数部份是几?
S=1/1／1980+1／1981+1／1982.+1/2006
1／1981+1／1982.+1/2006

令k=1/1980+...+1/2006
利用1/x+1/y>=2/(x+y), x>0, y>0
可得k>=27/1993>1/73
k<27/1980<1/73
所以73

猜你的题是：S=1/(1／1980+1／1981+1／1982.......+1/2006)
1/s=1/1980+1/2006+1/1981+1/2005+....+(1/1992+1/1994)+1/1993
=3986(1/1980/2006 +1/1981/2005 +....+1/1992/1994)+1/1993
1/s>3986(1/199...

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猜你的题是：S=1/(1／1980+1／1981+1／1982.......+1/2006)
1/s=1/1980+1/2006+1/1981+1/2005+....+(1/1992+1/1994)+1/1993
=3986(1/1980/2006 +1/1981/2005 +....+1/1992/1994)+1/1993
1/s>3986(1/1993^2)*13 +1/1993=27/1993 s<73.8148
1/s<3986*13/1980/2006+1/1993 s>73.81179
S取整＝73

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