You can imagine that if a vector is viewed from an angle, then its components will vary with the perspective.

你可以想象一下,如果换一个角度观察矢量,其分量会相应地发生变化

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Another way to represent a point in a plane is I've got a radius and I've got an angle from the x-axis, right, and that's a standard thing you might do.

平面上面的点的方法,也就是极坐标,上面那种方法其实是，如果你们喜欢我这么说的话,笛卡尔坐标表示法。

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