Find the derivative of f(x)=excos(x)f(x) = e^x \cos(x)f(x)=excos(x).
ex(cos(x)−sin(x))e^x(\cos(x) - \sin(x))ex(cos(x)−sin(x))
ex(cos(x)+sin(x))e^x(\cos(x) + \sin(x))ex(cos(x)+sin(x))
exsin(x)e^x \sin(x)exsin(x)
excos(x)e^x \cos(x)excos(x)