To determine if a function is odd or even, it is even when f(x) = f(-x), it is odd if f(x) = -f(-x)
Looking at x = 2, and x = -2
If x = 2, then f(x) = 4
If x = -2, then f(x) = -4
This does not satisfy for even.
If x =2, then f(x) = 4
Substitute -x,
-f(-x) = -f(-2) = -(-4) = 4
This satisfies for odd.
Hence the function is odd.
