8.E: Exercises
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In the following, polar coordinates (r,θ) for a point in the plane are given. Find the corresponding Cartesian coordinates.
- (2,\pi /4)
- (-2, \pi/4)
- (3, \pi/3)
- (-3, \pi/3)
- (2,5\pi /6)
- (-2, 11\pi /6)
- (2,\pi /2)
- (1,3\pi /2)
- (-3, 3\pi /4)
- (3, 5\pi /4)
- (-2, \pi /6)
Consider the following Cartesian coordinates (x, y). Find polar coordinates corresponding to these points.
- (-1,1)
- (\sqrt{3},-1)
- (0,2)
- (-5,0)
- (-2\sqrt{3},2)
- (2,-2)
- (-1,\sqrt{3})
- (-1,-\sqrt{3})
The following relations are written in terms of Cartesian coordinates (x, y). Rewrite them in terms of polar coordinates, (r,\theta ).
- y=x^2
- y=2x+6
- x^2+y^2=4
- x^2-y^2=1
Use a calculator or computer algebra system to graph the following polar relations.
- r=1-\sin (2\theta ),\:\theta\in [0,2\pi ]
- r=\sin (4\theta ),\:\theta\in [0,2\pi ]
- r=\cos (3\theta )+\sin (2\theta ),\: \theta\in [0,2\pi]
- r=\theta,\:\theta\in [0,15]
Graph the polar equation r = 1+\sinθ for θ ∈ [0, 2π].
Graph the polar equation r = 2+\sinθ for θ ∈ [0, 2π].
Graph the polar equation r = 1+2 \sinθ for θ ∈ [0, 2π].
Graph the polar equation r = 2+\sin(2θ) for θ ∈ [0, 2π].
Graph the polar equation r = 1+\sin(2θ) for θ ∈ [0, 2π].
Graph the polar equation r = 1+\sin(3θ) for θ ∈ [0, 2π].
Describe how to solve for r and θ in terms of x and y in polar coordinates.
This problem deals with parabolas, ellipses, and hyperbolas and their equations. Let l, e > 0 and consider r=\frac{l}{1\pm e\cos\theta}\nonumber Show that if e = 0, the graph of this equation gives a circle. Show that if 0 < e < 1, the graph is an ellipse, if e = 1 it is a parabola and if e > 1, it is a hyperbola.
The following are the cylindrical coordinates of points, (r,θ,z). Find the Cartesian and spherical coordinates of each point.
- (5,\frac{5\pi}{6},-3)
- (3,\frac{\pi}{3},4)
- (4,\frac{2\pi}{3},1)
- (2,\frac{3\pi}{4},-2)
- (3,\frac{3\pi}{2},-1)
- (8,\frac{11\pi}{6},-11)
The following are the Cartesian coordinates of points, (x, y,z). Find the cylindrical and spherical coordinates of these points.
- (\frac{5}{2}\sqrt{2},\frac{5}{2}\sqrt{2},-3)
- (\frac{3}{2},\frac{3}{2}\sqrt{3},2)
- (-\frac{5}{2}\sqrt{2},\frac{5}{2}\sqrt{2},11)
- (-\frac{5}{2},\frac{5}{2}\sqrt{3},23)
- (-\sqrt{3},-1,-5)
- (\frac{3}{2},-\frac{3}{2}\sqrt{3},-7)
- (\sqrt{2},\sqrt{6},2\sqrt{2})
- (-\frac{1}{2}\sqrt{3},\frac{3}{2},1)
- (-\frac{3}{4}\sqrt{2},\frac{3}{4}\sqrt{2},-\frac{3}{2}\sqrt{3})
- (-\sqrt{3}1,2\sqrt{3})
- (-\frac{1}{4}\sqrt{2},\frac{1}{4}\sqrt{6},-\frac{1}{2}\sqrt{2})
The following are spherical coordinates of points in the form (ρ,φ,θ). Find the Cartesian and cylindrical coordinates of each point.
- (4,\frac{\pi}{4},\frac{5\pi}{6})
- (2,\frac{\pi}{3},\frac{2\pi}{3})
- (3,\frac{5\pi}{6},\frac{3\pi}{2})
- (4,\frac{\pi}{2},\frac{7\pi}{4})
- (4,\frac{2\pi}{3},\frac{\pi}{6})
- (4,\frac{3\pi}{4},\frac{5\pi}{3})
Describe the surface φ = π/4 in Cartesian coordinates, where φ is the polar angle in spherical coordinates.
Describe the surface θ = π/4 in spherical coordinates, where θ is the angle measured from the positive x axis.
Describe the surface r=5 in Cartesian coordinates, where r is one of the cylindrical coordinates.
Describe the surface \rho =4 in Cartesian coordinates, where \rho is the distance to the origin.
Give the cone described by z=\sqrt{x^2+y^2} in cylindrical coordinates and in spherical coordinates.
The following are described in Cartesian coordinates. Rewrite them in terms of spherical coordinates.
- z=x^2+y^2
- x^2-y^2=1
- z^2+x^2+y^2=6
- z=\sqrt{x^2+y^2}
- y=x
- z=x
The following are described in Cartesian coordinates. Rewrite them in terms of cylindrical coordinates.
- z=x^2+y^2
- x^2-y^2=1
- z^2+x^2+y^2=6
- z=\sqrt{x^2+y^2}
- y=x
- z=x