Odd number squared.

[kk.]

i said n=1 in mine not the whole equation = 1

also im hardly going to fail kk considering im at a b level and im year 10. They made us to practise papers

As I said, it didn't help we all had different letters.
I'm only saying that I'm surprised that you haven't been taught it. You can't rely on your calculator or every tiny little sum, you wouldn't finish the paper. I'd advise you to ask your teacher tbh lol

[N!ck]

i said n=1 in mine not the whole equation = 1

also im hardly going to fail kk considering im at a b level and im year 10. They made us to practise papers

Well if n = 1 then the odd number that your squaring is 3.

(2n + 1) = 3

So when you do 2(2n^2 + 2n) + 1 with n = 1 you're getting the answer to 3^2.

2[2(1^2) + (2*1)] + 1

= 9