SEAMO 2017 — Paper C — Lớp 5–6 Câu hỏi 18

Tính $(\frac12+\frac13+\cdots+\frac1{2017})(1+\frac12+\cdots+\frac1{2016})-(1+\frac12+\cdots+\frac1{2017})(\frac12+\frac13+\cdots+\frac1{2016})$.