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Gilbert Strang, Calculus, 3rd edition (Wellesley-Cambridge Press; MIT OpenCourseWare RES.18-001) §2.4 The Derivative of the Sine and Cosine, #13 · Calculus · Differentiation rules

The unmarked points in Figure 2.11 are … and

The unmarked points in Figure 2.11 are and . Find the height and the area of triangle . Prove by areas that .

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Gilbert Strang, Calculus, 3rd edition (Wellesley-Cambridge Press; MIT OpenCourseWare RES.18-001) · §2.4 The Derivative of the Sine and Cosine, #13

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