The document discusses the lemniscate curve defined by the equation (x^2 + y^2)^2 = 2a^2(x^2 - y^2). It provides steps to graph this curve using a graphing calculator and describes how the parameter a affects the shape of the curve. It also determines the points where the tangent line is horizontal and discusses potential real-world applications of the lemniscate curve, such as racetracks and figure skating.
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