ExamBro
ExamBro
AP EAMCET · Maths · Basic of Mathematics

The remainder obtained when \((2 m+1)^{2 n}(m, n \in N)\) is divided by 8 is

  1. A \(1\)
  2. B \(2\)
  3. C \(3\)
  4. D \(4\)
Verified Solution

Answer & Solution

Correct Answer

(A) \(1\)

Step-by-step Solution

Detailed explanation

\((2m+1)^2 = 4m^2+4m+1 = 4m(m+1)+1\) \(m(m+1)\) is even, so \(m(m+1)=2k\) for some integer \(k\). \(4m(m+1)+1 = 4(2k)+1 = 8k+1\) \((2m+1)^2 \equiv 1 \pmod 8\) \((2m+1)^{2n} = ((2m+1)^2)^n \equiv (1)^n \pmod 8 \equiv 1 \pmod 8\) Remainder: \(1\)