What is the remainder of (32^31^301) when it is divided by 9?
2026
What is the remainder of (32^31^301) when it is divided by 9?
- A.
3
- B.
5
- C.
2
- D.
1
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Correct answer: B
Step 1: Reduce the base modulo 9. 32 ≡ 5 (mod 9), so the expression becomes 5^{31^{301}} (mod 9).
Step 2: Use Euler's theorem. φ(9)=6, and gcd(5,9)=1, so 5^6 ≡ 1 (mod 9).
Step 3: Reduce the exponent modulo 6. 31 ≡ 1 (mod 6), so 31^{301} ≡ 1^{301} ≡ 1 (mod 6).
Step 4: Conclude the remainder. Therefore 5^{31^{301}} ≡ 5^{1} ≡ 5 (mod 9), so the remainder is 5.