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How to calculate the rotation matrix in 3D in terms of an arbitrary axis of rotation? Given a unit vector $V=V_{x}e_{x}+V_{y}e_{y}+V_{z}e_{z}$ How to calculate the rotation matrix about that axis?

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    See e.g. [Wikipedia](http://en.wikipedia.org/wiki/Rotation_matrix#Rotation_matrix_from_axis_and_angle)2012-12-09
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    But the Wikipedia page just tells the formula . I want to know how to derive this2012-12-09
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    It's just a conjugation of the simple matrix for a rotation around the $z$-axis, which is effectively just 2 x 2 matrix, by another rotational matrix that rotates the North pole to the point $V$, which is a product of rotation in the theta-direction and the phi-direction to get where you need to get. Conjugation by $U$ is $URU^{-1}$ where the product is matrix product. It's possible ineffective to write these things without matrices so if you don't know matrices, this is a reason to learn them. At any rate, it's not really physics, it's linear algebra and geometry and a basic one.2012-12-09
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    thanks a lot. It's pretty simple . I think it can also be solved by considering an arbitrary vector ,taking the projection of that vector into the plane perpendicular to the axis of rotation and rotate that vector .2012-12-09
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    This is a math question and belongs on [math.se]2012-12-09

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