What is the derivative of the factorial function : -LSB- math -RSB- \ frac -LCB- d -RCB- -LCB- dx -RCB- \ left -LRB- x ! \ right -RRB- -LSB- / math -RSB- ?
What is the derivative of -LSB- math -RSB- x ^ x -LSB- / math -RSB- ?