The solutions to $7 x ^ { 4 } - 6 x ^ { 2 } + 1 = 0$ are $\pm \cos \theta$ and $\pm \cos \beta$. Which one of the following equations has solutions $\pm \sin \theta$ and $\pm \sin \beta$ ?
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The solutions to $7 x ^ { 4 } - 6 x ^ { 2 } + 1 = 0$ are $\pm \cos \theta$ and $\pm \cos \beta$.
Which one of the following equations has solutions $\pm \sin \theta$ and $\pm \sin \beta$ ?