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Find the nature of the stationery points of the curve xy+ 64x^2+1=0 and the coordinates of these points
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Your curve is
y = -, or, which is the same, y = .
First derivative is
= +
The first derivative has a zero at
= 64, or x = +/-.
There are two stationery points. One is (,). The other is (,).
Plot y =
The function is an odd function and has two branches.
The branch in the second quarter is convex downward.
The branch in the fourth quarter is convex upward.
On terminology see this Wikipedia article.