$\"\"$

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The general form of equation is $\"\"$ .

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The rotation equation is $\"\"$ .

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Where $\"\"$ , $\"\"$ ,

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$\"\"$ , $\"\"$ , $\"\"$ and $\"\"$ .

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Find $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$ .

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$\"\"$

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$\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$ .

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$\"\"$

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$\"\"$

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Apply formula: $\"\"$ .

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$\"\"$

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Therefore, the value of $\"\"$ is invariant.

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$\"\"$

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$\"\"$ , hence the value of $\"\"$ is invariant.