What is the derivative with respect to x -LSB- math -RSB- x \ sin -LRB- y -RRB- + y \ cos -LRB- x -RRB- = 0 -LSB- / math -RSB- ?
What is -LSB- math -RSB- \ frac -LCB- d -RCB- -LCB- dx -RCB- \ left -LRB- \ sin -LRB- 2x -RRB- \ cos -LRB- 2y -RRB- = 0 \ right -RRB- -LSB- / math -RSB- ?