Derivative of the Sine and Cosine
Many machine learning algorithms involve an optimization process for different purposes. Optimization refers to the problem of minimizing or maximizing an objective function by altering the value of its inputs.
Optimization algorithms rely on the use of derivatives in order to understand how to alter (increase or decrease) the input values to the objective function, in order to minimize or maximize it. It is, therefore, important that the objective function under consideration is differentiable.
The two fundamental trigonometric functions, the sine and cosine, offer a good opportunity to understand the manoeuvres that might be required in finding the derivatives of differentiable functions. These two functions become especially important if we think of them as the