Chapter 11: Problem 6
Describe the similarities and differences between the parametric equations \(x=t, y=t^{2}\) and \(x=-t, y=t^{2},\) where \(t \geq 0\) in each case.
Chapter 11: Problem 6
Describe the similarities and differences between the parametric equations \(x=t, y=t^{2}\) and \(x=-t, y=t^{2},\) where \(t \geq 0\) in each case.
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Get started for freeA focal chord of a conic section is a line through a focus joining two points of the curve. The latus rectum is the focal chord perpendicular to the major axis of the conic. Prove the following properties. Let \(L\) be the latus rectum of the parabola \(y^{2}=4 p x,\) for \(p>0\) Let \(F\) be the focus of the parabola, \(P\) be any point on the parabola to the left of \(L,\) and \(D\) be the (shortest) distance between \(P\) and \(L\) Show that for all \(P, D+|F P|\) is a constant. Find the constant.
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Graph the following equations. Then use arrows and labeled points to indicate how the curve is generated as \(\theta\) increases from 0 to \(2 \pi\). $$r=\frac{3}{1-\cos \theta}$$
Consider the following sequence of problems related to grazing goats tied to a rope. A circular concrete slab of unit radius is surrounded by grass. A goat is tied to the edge of the slab with a rope of length \(0 \leq a \leq 2\) (see figure). What is the area of the grassy region that the goat can graze? Note that the rope can extend over the concrete slab. Check your answer with the special cases \(a=0\) and \(a=2\)
What is the equation of the standard parabola with its vertex at the origin that opens downward?
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