=(-1²+2²)+(-3²+4²)+(-5²+6²)-······(-99²+100²)=(2+1)(2-1)+(4+3)+(4-3)+,+(100+99)+(100-99)=1+2+3+4+...+99+100=(1+100)+(2+99)+...+(50+51)=101x50=5050希望能帮...