Homework Help: Coordinate Systems

1. Oct 15, 2008

STLCards002

1. The problem statement, all variables and given/known data
Graph the surface in R3

2. Relevant equations
Spherical equation $$\rho$$ = 2asin($$\varphi$$)

3. The attempt at a solution
I think its just a sphere with a radius of 2
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1. The problem statement, all variables and given/known data
Graph the solid whose given coordinates satisfy the inequalities

2. Relevant equations
a) 0 $$\leq$$ r $$\leq$$ 3, 0 $$\leq$$ $$\theta$$ $$\leq$$ $$\pi$$/2, -1 $$\leq$$ z $$\leq$$ 2
b) 2r $$\leq$$ z $$\leq$$ 5 - 3r

3. The attempt at a solution
I figure these are cylinders because of variables used to describe the coordinates but besides that I'm having trouble know what to use the inequalities for
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1. The problem statement, all variables and given/known data
Graph the solid whose given coordinates satisfy the inequalities

2. Relevant equations
a) 0 $$\leq$$ $$\rho$$ $$\leq$$ 1, 0 $$\leq$$ $$\theta$$ $$\leq$$ $$\pi$$/2,
b) 0 $$\leq$$ $$\rho$$ $$\leq$$ 2/cos$$\varphi$$, 0 $$\leq$$ $$\varphi$$ $$\leq$$ $$\pi$$/4

3. The attempt at a solution
Spheres, but same problem as with the others, I'm just not doing well at understanding how to use the inequalities to graph it

2. Oct 16, 2008

tiny-tim

Hi STLCards002!

Sorry, but everything is wrong.

The only thing I can suggest is that you draw a nice big diagram (take up a whole page), with x y and z axes marked, and just draw in the boundaries.

If it helps, pretend the inequalities are equalities … that will give you the boundaries, and you can work out which parts to shade, later.

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