Obtain other zeroes of the polynomial $P(x) = 2x^4 - x^3 - 11x^2 + 5x + 5$ if two of its zeroes are $\sqrt{5}$ and $-\sqrt{5}$.

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Step 1: Since $\sqrt{5}$ and $-\sqrt{5}$ are zeroes of $P(x)$, so $(x - \sqrt{5})(x + \sqrt{5}) = (x^2 - 5)$ is a factor of $P(x)$.
Step 2: Dividing: $(2x^4 - x^3 - 11x^2 + 5x + 5) \div (x^2 - 5) = 2x^2 - x - 1$
Step 3: $2x^2 - x - 1 = (2x + 1)(x - 1)$
Step 4: Other zeroes of $P(x)$ are $1$ and $-\frac{1}{2}$.

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