New assignment: Using vector method prove that \sin(A + B) = \sinA\cosB + \cosA\sinB
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We have: $$\sin(A - B) = \sin A \cos B - \cos A \sin B$$ Now, let's consider two vectors $\vec{A}$ and $\vec{B}$ with magnitudes $|\vec{A}|$ and $|\vec{B}|$, and the angle between them as $\theta$. We can represent $\sin A$ and $\sin B$ as the components of Show more…
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