计算1/1×2+1/2×3+1/3×4+1/4×5+……+1/2011×2012=?
问题描述:
计算1/1×2+1/2×3+1/3×4+1/4×5+……+1/2011×2012=?
答
1/1×2+1/2×3+1/3×4+1/4×5+……+1/2011×2012
=1/1-1/2+1/2-1/3+1/3-1/4+.+1/2011-1/2012
=1-1/2012
=2011/2012