\"\" \ \

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The points on the plane are \"\" and \"\".

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The points \"\" are lies on the plane then their vectors \"\" are lie on the same plane.

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If \"\" and \"\" are the two points then the component form of vector  \"\" is

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\"\"

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\"\"

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If \"\" and \"\" are the two points then the component form  of vector  \"\" is

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\"\"

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\"\".

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Consider \"\".

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\"\"

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\"\".

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From geometric properties of the cross product, \"\" is perpendicular to both \"\" and \"\".

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Thus  \"\" is perpendicular to plane passing through the points \"\" and \"\".

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\"\" \ \

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Area of the \"\" is half of the area of the parallelogram with adjacent sides \"\" and \"\".

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Area of the parallelogram with adjacent sides \"\" and \"\" is \"\".

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Area of the \"\" is

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\"\"

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Area of the \"\" is \"\" sq-units.

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\"\"

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\"\" is a non-zero vector perpendicular to plane passing through the

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points \"\" and \"\".

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Area of the \"\" is \"\" sq-units.