1. F

    A question about converting cylindrical coordinates to rectangular coordinates

    I have a problem figuring something out when it comes to converting cylindrical to 3D rectangular coordinates. the formulas for converting are as follows: x = r cos theta y = r sin theta z = z If we're just using basic trigonometry to figure out the sides of the triangle of which the angle...
  2. F

    A question about cylindrical coordinates

    So cylindrical coordinates are basically a 3D representation of polar coordinates. Since with polar coordinates we can use basic trigonometry to figure out the length of the triangle sides x or y and therefore convert from polar to 2D rectangular, the same is true for converting from cylindrical...
  3. Z

    3D polar coordinates problem

    Find the volume below z = r, above the x-y plane, and inside r = cos \theta. Answer: 4/9 Is there anyone online tool I could use to plot the 3d polar coordinates? I couldn't approach the problem without any visual clues...
  4. Z

    Double Integration with Polar Coordinates

    Find the volume inside both r = 1 and r^2 + z^2 = 4. Answer: 32 * pi/3 - 4 * sqrt(3) * pi This is what I came up but the result is only half of the correct anbswer.. Any tips would be much appreciated. \int_{0}^{2\pi}\int_{0}^{1} sqrt(4-r^2) r drd\theta
  5. L

    Integer coordinates in a sphere

    Given a sphere of integer radius R, how many integer coordinates (a, b, c) at most does it contain?
  6. H

    3D system to a 2D system coordinates conversion

    Hi all, I need help with a geometry problem for a computer program that I am developing: I work in a 3D (x,y,z) Euclidian space - origin OO. Within this space there is a 2D Euclidian plane with its own independent (x,y) coordinates system. The 2D plane can be positioned anywhere...
  7. S

    The length of a curve given in polar coordinates

    I do not know hot to solve this problem. I have a function given in polar coordinates and I would like to calculate the length of the curve for angles from 0 to 2pi. r\left(\theta \right)=sin^2\:\frac{3\cdot \theta }{2} \theta \in \left[0,2\pi \right] I would be greatful if anyone give...
  8. M

    Plane Coordinates

    The attached figure illustrates a rectangular coordinate system xy generated by the unit vectors of the canonical base \vec{i} and \vec{j} and a system of coordinates non-rectangular {x}'{y}' generated by the unit vectors \vec{u} and \vec{v} (\left \| \vec{u} \right \| = \left \| \vec{v} \right...
  9. Monox D. I-Fly

    [ASK] About Circles in Coordinates

    3. A(a,b), B(-a,-b), and C is plane XOY. P moves along with curve C. If the multiplication product of PA's and PB's gradients are always k, C is a circle only if k = ...? 4. The radius of a circle which meets X-axis at (6,0) and meets the curve y=\sqrt{3x} at one point is .... 5. A circle...
  10. D

    Solve double integral by converting to polar coordinates
  11. K

    polar coordinates and right triangles

    i began learning linear algebra on khan academy and done a "Add vectors: magnitude & direction to component" quiz but i got a bit confused from something i saw on another website and that question on the quiz(in the attached picture). on math is fun site...
  12. H

    How to calculate x/y coordinates for rotated triangle?

    (Disclaimer: I have zero math skills, so I will try to explain my problem to the best of my abilities in a layman's terms.) Hi, I have a triangle defined as three pairs of coordinates of x/y. I then receive the value angle (expressed as a radian), and I calculate sin and con from that...
  13. E

    Constructing 3D roof + footprint from one line.

    Help solving this problem of mine is much apprecierad!! I've seen it done before, but I'm not sure how to tackle it myself. (Please have a look at the attached image if my explanation is utterly rubbish which it most definetly is) I have a multiple lines (one for each building) going from...
  14. C

    Calculate co-ordinates of embedded rectangle on rotation of parent rectangle

    OK... too many years since school but I want to know the mathematical formulae to calulcate the co-ordinates of the green rectangle (X,Y of each corner) when he known values are: Width and Height of parent (blue) rectangle Rotation in degrees or radians about the centre of the rectangle...
  15. P

    Polar coordinates - why does starting angle make a difference?

    A circle in the xy-plane at (1, 1) and radius $\sqrt{2}$. $\iint_{D}^{} (x^2 + y^2) \, dA$ The limits $\int_{0}^{2 \pi} \int_{0}^{2(cos(\theta)+sin(\theta)} (r^2) \, r \, dr \, d \theta$ give the wrong answer $12 \pi$. The limits $\int_{\frac{-\pi}{4}}^{\frac{3 \pi}{4}}...
  16. J

    Integral calculation based on coordinates / Area under Curve calculation

    Hello all, I am looking for an easy solution to integral calculation based on coordinates. For example, what is the surface under: (0,5), (15,3), (30,2), (45, 5)? Any suggestions on how to also automate the calculation in Excel of SPSS? Thanks, Joske
  17. Y

    Trilinear Coordinates of Schiffler Point ?

    Hello guys, I know trilinear coordinates of Schiffler point, but I don't know how to get them. Do you have any source about getting trilinear coordinates of Schiffler?
  18. happy21

    Coordinates of cicumcentre and orthocentre

    Hello all, How can we derive the following formulae of the coordinates? Given: A, B & C angles of a triangle and the coordinates of the vertices of the triangle are (X_{1}, Y_{1}), (X_{2}, Y_{2}), (X_{3}, Y_{3}) 1. Circumcentre of the triangle is: (\frac{X_{1}\sin 2A+X_{2}\sin...
  19. Y

    Cartesian Coordinates of Schiffler Point?

    I know where is Schiffler point on triangle but what if we think cartesian coordinates of Schiffler Point; I couldnt find it and I am waiting for your help guys.
  20. M

    coordinates and quadrangle

    Hi, How Can I find coordinates of points C,D. I have lenght a,b,c,d and angles k1,k2,k3,k4 and coordinates A,B points.