Write a third-degree polynomial function whose zeros are 1, −3, and 4.

Recall that zeroes can be transformed into factors by subtracting them from x. This gives us the following factors:

(x - 1)(x + 3)(x - 4)

Now, if you multiply the first two factors together, you get the following:

(x² + 2x - 3)

Multiply that by the last factor, (x - 4), and you get this:

(x³ + 2x² - 3x - 4x² - 8x + 12)

This can be simplified:

(x³ - 2x² - 11x + 12)

And there's your final answer. Hope this helped!