To identify the odd function from the given options, we can recall that a function \( f(x) \) is considered odd if it satisfies the condition \( f(-x) = -f(x) \) for all \( x \) in its domain.
Let's evaluate each function:
-
\( f(x) = 2(x+1)^3 \):
- \( f(-x) = 2(-x + 1)^3 = 2(1 - x)^3 \) (which does not equal \(-f(x)\)).
-
\( f(x) = x^4 \):
- \( f(-x) = (-x)^4 = x^4 \) (this is equal to \( f(x) \), so this function is even).
-
\( f(x) = 3x^2 \):
- \( f(-x) = 3(-x)^2 = 3x^2 \) (this is equal to \( f(x) \), so this function is even).
-
\( f(x) = 2x^3 \):
- \( f(-x) = 2(-x)^3 = -2x^3 = -f(x) \) (this satisfies the condition for odd functions).
Therefore, the odd function among the choices is:
f(x) = 2x^3.