1/1*2+1/2*3+1/3*4+.+1/99*100=?

1*2/1+2*3/1+3*4/1+.98*99/1+99*100/1=? 1*1*1+2*2*2+3*3*3+4*4*4+.+99*99*99*+100*100*100=? 1/1×2+1/2×3+1/3×4+1/4×5+.+1/98×99+1/99×100=? 1/1*2+1/2*3+1/3*4+1/4*5+.1/98*99+1/99*100=? 1/1*2+1/2*3+1/3*4+1/4*5.1/99*100= 1/1*2+1/2*3+1/3*4+…+1/99*100=? 1/1*2+1/2*3+1/3*4+.1/99*100=? (-1*1\2)+(-1\2*1\3)+(-1\3*1\4)+.+(-1\99*1\100) (1-1/2)(1-1/3)(1-1/4).(1-1/99)(1-1/100)等于? 1/1*2*3*4+1/2*3*4*5+...+1/97*98*99*100=? 1/1*2+1/2*3+1/3*4~+1/98*99+1/99*100 *=乘以 |1/3-1/2|+|1/4-1/3|+|1/5+1/4|+...+|1/100-1/99|=?有谁能解急