Number of points required for getting exact answer using Gauss quadrature for a non-polynomial function.

Question

I have been trying to evaluate the following integral using Gauss Legendre quadrature.

\begin{equation} f(x) = \int_{1}^{0.8}\frac{1}{0.3-x^4}dx \end{equation}

I know that the number of Gauss points required for a polynomial of degree $p$ is given by $p = 2n-1$, where $n$ is the number of points required. But since this function is not a polynomial, how can I determine the number of points required for getting the exact value of the integral?