Figure 4.3.3. Which Graph Is Extra? Consider the curve C C given by the polar equation r= 1+2cosθ, r = 1 + 2 cos ⁡ θ, for 0 ≤ θ <2π. 0 ≤ θ <2 π . Find the Cartesian coordinates for the point on the ...

But there's a trick that uses calculus and the magic of dividing by zero. Instead of finding the tangent line, it's much easier to find the slope of a line that touches the curve at two points. If ...