The previous section defined curves based on parametric equations. In this section we'll employ the techniques of calculus to study these curves. We are still interested in lines tangent to points on ...

$explain = "For \( t = \pi \), we have \( c(\pi) = (-1, 0) \). As t increases from \( \pi \) to \( 2\pi \), the x-coordinate of \( c(t) \) increases from -1 to 1, and ...