if any se positive engineer and N2N^2 is divisible by 12 then prove that n is divisible by 6

Answer: Hence, it is proved that nn is divisible by 66.

Step-by-step solution

Step 1: Analyze the divisibility of n2n^2

We are given that nn is a positive integer and n2n^2 is divisible by 1212. Writing 1212 as a product of prime powers, we have 12=22×312 = 2^2 \times 3. Since 1212 divides n2n^2, it follows that both 22 and 33 divide n2n^2.

Step 2: Apply Theorem on divisibility by prime 2

Since 1212 divides n2n^2, 22 is a prime dividing n2n^2. By the Fundamental Theorem of Arithmetic (Theorem 1.2: if a prime pp divides a2a^2, then pp divides aa), since 22 is a prime number and 2∣n22 \mid n^2, it follows that 22 must divide nn.

Step 3: Apply Theorem on divisibility by prime 3

Similarly, 33 is a prime factor of 1212, so 33 divides n2n^2. Applying the same theorem (if a prime pp divides a2a^2, then pp divides aa), since 33 is prime and 3∣n23 \mid n^2, it follows that 33 must divide nn.

Step 4: Conclude divisibility by 6

We have shown that both 22 and 33 divide nn. Since 22 and 33 are distinct prime numbers (coprime, with gcd⁡(2,3)=1\gcd(2, 3) = 1), their product 2×3=62 \times 3 = 6 must also divide nn. Hence, nn is divisible by 66.

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