How does one evaluate -LSB- math -RSB- \ displaystyle \ int \ frac -LCB- \ mathrm -LCB- d -RCB- x -RCB- -LCB- \ sin ^ 3 x - \ cos ^ 3 x -RCB- -LSB- / math -RSB- ?
How do I evaluate the integral -LSB- math -RSB- \ displaystyle \ int \ frac -LCB- \ sin x -RCB- -LCB- \ sin 4x -RCB- \ , dx -LSB- / math -RSB- ?