若f(n)=1+1/2+1/3...1/n,则f(2`k+1)比f(2`k)增加了几项?

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若f(n)=1+1/2+1/3...1/n,则f(2`k+1)比f(2`k)增加了几项?

若f(n)=1+1/2+1/3...1/n,则f(2`k+1)比f(2`k)增加了几项?
若f(n)=1+1/2+1/3...1/n,则f(2`k+1)比f(2`k)增加了几项?

若f(n)=1+1/2+1/3...1/n,则f(2`k+1)比f(2`k)增加了几项?
f(n)有n项,f(2k+1)有2k+1项,比前面的多了2k+1-n项.

f(2`k+1)有2`k+1项
f(2`k)有2`k项
则f(2`k+1)比f(2`k)增加了2`k+1-2`k=1项

楼主的意思是2得(k+1)次方比2得k次方多几项是吗?
其实就是增加了2得(k+1)次方减去2得k次方那么多项呗。
其实就是2得k次方而已。
一道障眼法的题!

f(2^k)有2^k项
f[2^(k+1)]有2^(k+1)项
所以增加了2^(k+1)-2^k项
2^(k+1)-2^k
=2^k*2^1-2^k
=2^k*(2-1)
=2^k
所以增加了2^k项