2/3x5+2/5x7+…+2/31x33
问题描述：
2/3x5+2/5x7+…+2/31x33
答
2/3x5+2/5x7+…+2/31x33=(5-3)/3*5+(7-5)/5x7+…+(33-31)/31x33=(5/3*5-3/3*5)+(7/5x7-5/5x7)+…+(33/31x33-31/31x33)=(1/3-1/5)+(1/5-1/7)+…+(1/31-1/33)=1/3-1/5+1/5-1/7+…+1/31-1/33=1/3+(-1/5+1/5)+(-1/7+1/7)...能再简单一些吗？2/3x5+2/5x7+…+2/31x33=(5-3)/3*5+(7-5)/5x7+…+(33-31)/31x33=1/3-1/5+1/5-1/7+…+1/31-1/33=1/3-1/33=10/33 可以简化步骤，不能简单，只是为了让你看懂。