5. The Formulas for Symmetric Functions
If
and
,
. 1 → [
1]:
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1 →, 3→
Theorem 14. .
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1 →, 5→
Theorem 15. .
Compared to 14, this is a little different.
Theorem 16. ,
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Proof. By the definition of , there clearly is:
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Let , 1→ the rest.
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Special:
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From , it’s easy to get:
. .
The extension can be obtained with .
,
Theorem 17. .
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Proof. Proof of the third equation. From and the first equation,
it can be seen that and have the same thing:
11 the expression.
The same conclusion can be obtained by combining definition of and 11.
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,
Theorem 18. ,
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,
Theorem 19. .
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Theorem 20. ,
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Theorem 21. ,
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Proof.
,
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