In this post, we establish the formulas of the differentiation of trigonometric formulas, \frac{d}{dx} sin(x) = cos(x) , and \frac{d}{dx} cos(x) = -sin(x) by numerical estimations of the limits and informal proofs based on geometric constructions. This syllabus dot point is a part of the QCE Maths Methods course under the topic Further Differentiation and Applications 2 and sub-part Calculus of Trigonometric Functions, specifically differentiation of trigonometric functions.
Derivatives of trigonometric functions
Establishing the derivatives
Proof of the derivatives of sin(x)
