Which statement correctly describes the end behavior of f(x) = -9x^4 + 3x^3 + 3x^2 - 1?

Question

As x goes to infinity, f(x) goes to infinity, and as x goes to negative infinity, f(x) goes to infinity.
As x goes to infinity, f(x) goes to negative infinity, and as x goes to negative infinity, f(x) goes to infinity.
As x goes to infinity, f(x) goes to infinity, and as x goes to negative infinity, f(x) goes to negative infinity.
As x goes to infinity, f(x) goes to negative infinity, and as x goes to negative infinity, f(x) goes to negative infinity.

Answer 1

As x goes to infinity, f(x) goes to negative infinity, and as x goes to negative infinity, f(x) goes to negative infinity.

To the 4th power is "w" shaped. Then, because it is a negative coefficient, it is going to negative infinity so it is an upside down "w".