Assignment #4

(Due October 6)

4.4.{63,64,65,69,70,71}

4.5.{60,63,73}

4.6.{59,60,61,62,64}

Folium of Descartes problem:

The picture above has the equation 2x^3 + 2y^3 = 9xy.  The shape is called the "Folium of Descartes."

• Show that the point (2,1) is on the curve, and find the slope of the tangent line at that point.
• At which point(s) (x,y) is dy/dx undefined?  Explain geometrically why each point does not have a valid dy/dx value.

Best wishes,

-jason