数学题1/(3*5*7)+1/(5*7*9)+1/(7*9*11)+1/(9*11*13)+1/(11*13*15)

问题描述:

数学题1/(3*5*7)+1/(5*7*9)+1/(7*9*11)+1/(9*11*13)+1/(11*13*15)

1/(3*5*7)=[1(3*5)-1/(5*7)]/4
因此题目结论是:
1/(3*5*7)+1/(5*7*9)+1/(7*9*11)+1/(9*11*13)+1/(11*13*15)
={[1(3*5)-1/(5*7)]+[1/(5*7)-1/(7*9)]+^……+
[ 1/(11*13)-1/(13*15)]}/4
=1/65