I barely remember trigonometry and I’m unclear about how the difference between sin(x + delta x) and sin(x) becomes delta sin(x). What does delta sin(x) mean and how do we arrive at that reduced form?

Hi @MikeML

Good question! \Delta \sin(x) represents the change in the sine value when x is incremented by \Delta x. This is expressed as:

\Delta \sin(x) = \sin(x + \Delta x) - \sin(x).

This change helps in finding the derivative of \sin(x), which is the rate of change of the sine function on x. As \Delta x approaches 0, \Delta \sin(x) / \Delta x approaches \cos(x), leading to the derivative \frac{d}{dx}\sin(x) = \cos(x).

Hope it helps!

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