(1/50-1)(1/49-1)(1/48-1).(1/4-1)(1/3-1)(1/2-1)简便算法!快!详细过程!

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(1/50-1)(1/49-1)(1/48-1).(1/4-1)(1/3-1)(1/2-1)简便算法!快!详细过程!(1/50-1)(1/49-1)(1/48-1).(1/4-1)(1/3-1)(1/

(1/50-1)(1/49-1)(1/48-1).(1/4-1)(1/3-1)(1/2-1)简便算法!快!详细过程!
(1/50-1)(1/49-1)(1/48-1).(1/4-1)(1/3-1)(1/2-1)
简便算法!快!详细过程!

(1/50-1)(1/49-1)(1/48-1).(1/4-1)(1/3-1)(1/2-1)简便算法!快!详细过程!
(1/50-1)(1/49-1)(1/48-1).(1/4-1)(1/3-1)(1/2-1)
= (-1)^49 * (1-1/50)(1-1/49)...(1-1/2)
= (-1) * (49/50)(48/49)...(2/3)(1/2)
= (-1) * (49*48*.*2*1)/(50*49*48*.*3*2)
= (-1) * (1)/(50)
= -1/50

(1/50-1)(1/49-1)(1/48-1).......(1/4-1)(1/3-1)(1/2-1)
=1/2*2/3*3/4*...48/49*49/50
=1/50