Question

Find counter examples to disprove the following statement.
If n is a whole number then $2n^2+11$ is a prime.

Answer 1

Given n is a whole number then $2n^2+11$

Let n=$12$

Then $2\times {12}^2+11=288+11=299$

A prime number can be divided, without a remainder, only by itself and by 1.

So $299$ is divisible by $13$ and $23$ then this is not a prime number

So disprove statement $2n^2+11$ is a prime

If n is a whole number then $2n^2+11$ is not a prime number