The quartic with implicit equation
(1)
|
The bow has vertical tangents at
and horizontal tangents at
.
Its curvature is implicitly given by
(2)
|
The area enclosed by the two loops is given by
(3)
| |||
(4)
|
(OEIS A118321).
The portion of the curve bounding the two loops has approximate perimeter
(5)
|
(OEIS A118322).