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Mathematical proof
Paper 2 · Mathematical proof · Number, ratio and units
1 / 60
Consider the statement: “For every positive integer
n
n
n
, if
n
n
n
is odd then
n
2
+
4
n^2 + 4
n
2
+
4
is prime.” Which value of
n
n
n
is a counterexample to this statement?
A
n
=
1
n = 1
n
=
1
B
n
=
2
n = 2
n
=
2
C
n
=
5
n = 5
n
=
5
D
n
=
7
n = 7
n
=
7
E
n
=
9
n = 9
n
=
9
F
n
=
13
n = 13
n
=
13
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