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Solution

✅ Correct Option: 2

The expression (x+296×298)(x + 296 \times 298) needs to be a perfect square.

Notice that 296296 and 298298 are consecutive even numbers around 297297:

296=297−1296 = 297 - 1

298=297+1298 = 297 + 1


Using the formula (a−b)(a+b)=a2−b2(a - b)(a + b) = a^2 - b^2 with a=297a = 297 and b=1b = 1:

296×298=(297−1)(297+1)296 \times 298 = (297 - 1)(297 + 1)

=2972−12= 297^2 - 1^2

=2972−1= 297^2 - 1


Substituting back into the original expression:

x+296×298=x+(2972−1)x + 296 \times 298 = x + (297^2 - 1)

=x+2972−1= x + 297^2 - 1

=2972+(x−1)= 297^2 + (x - 1)


For this to be a perfect square, the simplest case is when it equals 2972297^2 exactly.

This occurs when:

x−1=0x - 1 = 0

x=1x = 1

Therefore, the value of xx is 11.

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