The derivative of f(x) = sin(x) is g(x) = cos(x)

What is the trace of B representing? Looking at the animation... What is the derivative of f(x)? If you change the input of f(x) how does the trace of B change? Or in other words how does the derivative of f(x) change? For example try inputing x^2 for f(x). What does the trace of B look like now?