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Show that 6^3-1 is divisible by 5 using our identities

User Lucacerone
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2 Answers

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\displaystyle 6^3 - 1 = 216 - 1 = 215

The number 215 is divisible by 5 because it ends in 5, according to the divisibility rules.

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User Slava Eremenko
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Answer:

Explanation:

a³-b³=(a-b)(a²+ab+b²)

6³-1=6³-1³=(6-1)(6²+6*1+1²)=5×43

so 6³-1 is divisible by 5.

User Bendaf
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