The zeros of the function $f(x) = 9x^3 + 39x^2 - 26x + 20$ are:

$x = -5, \quad x = \frac{1}{3} - \frac{\sqrt{3}}{3}i, \quad x = \frac{1}{3} + \frac{\sqrt{3}}{3}i$

These are the exact values, including one real zero and two complex zeros.

Would you like further clarification or more details on these solutions?

Here are 5 related questions:

1. How can you verify if the solutions are correct?
2. What is the significance of real vs complex zeros in polynomial functions?
3. How does the degree of the polynomial relate to the number of zeros?
4. Can you find the sum of the real and complex zeros of a cubic function?
5. How do the factors of this cubic function relate to its zeros?

Tip: Complex roots always occur in conjugate pairs if the polynomial has real coefficients.