✔ 最佳答案
1. a^n+4 - a^3n
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a^3n+3 - a^n+7
(a^n)( a^4) – (a^n)(a^n)(a^n)
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(a^n)(a^n)(a^n)(a^3) – (a^n) (a^7)
(a^n)[( a^4) – (a^n)(a^n)]
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(a^n)[(a^n)(a^n)(a^3) – (a^7)]
[( a^4) – (a^n)(a^n)]
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[(a^n)(a^n)(a^3) – (a^7)]
[( a^4) – (a^n)(a^n)]
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[(a^n)(a^n)(a^3) – (a^3)(a^4)]
[( a^4) – (a^n)(a^n)]
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(a^3) [(a^n)(a^n) – (a^4)]
- 1[(a^n)(a^n)- ( a^4) ]
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(a^3) [(a^n)(a^n) – (a^4)]
- 1
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(a^3)
2a,若n是正整數 , 證明 2^n x 3^n+1= 3.6^n
2^n x 3^n+1= 3.6^n
(2^n) (3^n) (3^1)= 3.6^n
(6^n)(3)= (3)(6^n)
2b,求 2^n x 3^n+1
------------------- 的值
6^n-2
(2^n)(3^n)(3^1)
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(6^n)/(6^2)
(6^n)(3^1)
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(6^n)/(6^2)
(3^1)
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1/(6^2)
(3^1)(6^2)
(3)(36)
= 108