Why does zero factorial -LRB- 0 ! -RRB- equal one -LRB- 1 -RRB- ?
Is -LSB- math -RSB- \ frac -LCB- 0 -RCB- -LCB- 0 -RCB- -LSB- / math -RSB- equal to -LSB- math -RSB- \ frac -LCB- 0 -RCB- -LCB- 0 -RCB- -LSB- / math -RSB- ?