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Proof by mathematical induction — Question 4

QCAA 2025, Paper 2 · 1 mark

Q4 · 2025 · Technology-activeSimple familiar1 mark

QUESTION 4

The expression 9×2n+1+2n9\times 2^{n+1}+2^n, where n∈Z+n\in\mathbb Z^+, is divisible by
(A)
1010
(B)
1111
(C)
1818
(D)
1919
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