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Proof and induction — Question 4

Original QCE Vault practice · 1 mark

Q4 · Practice questionSimple familiar1 mark

QUESTION 4

Which expression is divisible by 5 for every positive integer $n$ ?

(A)

5^n-1

(B)

4^n-1

(C)

2^{2n}-1

(D)

6^n-1

ABCD

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