8e9c44…: “Ahead of the maroon icosahedron”

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Consider the function $F(x,y) = 4x^2-y^2+2$ . A representation of several curves are given below. Select all that are a part of a level curve of $F(x,y)$ .

$y=x$ $y=2x$ $y=4x$ $4x^2-y^2=14$ $\vec {r}(t) =\vector {t,4t+1}$ $\vec {r}(t) =\vector {t^2,2t^2}$ $\vec {r}(t) =\vector {t^2,2t^2,2}$