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จากโจทย์ |
z |
= |
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เขียนให้อยู่ในรูปเชิงขั้วจะได้ |
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z |
= |
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จากสูตร |
zn |
= |
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จะได้ |
z12 |
= |
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= |
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= |
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= |
531441(-1 + 0i) |
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ดังนั้น |
z12 |
= |
-531441 |
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ให้ |
z1 |
= |
1 - i |
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จะได้ |
z1 |
= |
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และให้ |
z2 |
= |
-1 - i |
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จะได้ |
z2 |
= |
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นั่นคือ |
(1 - i)6 |
= |
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= |
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= |
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= |
8(0 + i) |
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ดังนั้น |
(1 - i)6 |
= |
8i |
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และ |
(-1 - i)4 |
= |
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= |
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= |
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= |
4(-1 + 0i) |
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ดังนั้น |
(-1 - i)4 |
= |
-4 |
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จะได้ |
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= |
-2i |
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