Hello from MrBillDoesMath
Answer:
See below
Discussion:
Note the Question incorrectly shows (2n^2 +1) ^ 2. It should be (2n + 1) ^2.
So
(2 n + 1) ^2 - (2n +1) =
4n^2 + 4n + 1 - 2n - 1 = ( -1 + 1 = 0)
4n^2 + 4n -2n + (1-1) =
4(X) = 2 (2X)
Key point. The end result of the evaluation is a multiple of 2 so the result is an even integer.
Thank you,
Mr. B