1. Y

    Finding planes that intersect spheres in 3D vector Geometry

    If you are given the sphere: x²+y²+z²+x-6z=0 and the plane x+y+=0 how do you find the planes which are parallell to that plane which intersect the sphere to create circles of radius 3. Any help would be much appreciated. Thanks!
  2. S

    how to know that the point is intersect with the mesh?

    hello friends...i'm new here... i have a problem in determining the mesh that intersect with the point... i have 1 point and 2 mesh... i have tried many times searching in the google, but it doesn't work... i hope anyone here can help me to solve my problem..?? thank you...(Happy)
  3. K

    Do these lines intersect? If so...

    Here's a practice problem. Given the lines x = (1,2,-1) + t(3,1,2) y = (9,0,1) + s(-1,2,1) a) determine whether they intersect b) if they intersect find the equation of the plane determined by the lines --------- Could somebody check my answer please? I have decided that they do...
  4. A

    Altitudes of tetrahedron intersect, coordinate vectors

    A tetrahedron has vertices A, B, C and D with coordinate vectors for the points being: \mathbf{a}=\begin{pmatrix}0\\1\\2\end{pmatrix},\ \mathbf{b}=\begin{pmatrix}-1\\4\\1\end{pmatrix}, \mathbf{c}= \begin{pmatrix}1\\0\\3\end{pmatrix},\ and\ \mathbf{d}=\begin{pmatrix}-3\\1\\2\end{pmatrix}...
  5. K

    How 3 planes intersect.

    Hey, thanks for coming into my thread! I have a problem. I am given 3 equations of planes, in the form Ax + By + Cz + D = 0, and am being asked how they are intersecting. Here are the 3 equations: 1. x + 2y + 3z + 4 = 0 2. x - y - 3z - 2 = 0 3. x + 5y + 9z + 10 = 0 I decided to run it through...
  6. P

    Vector Plane Problem

    This question has stumped me, it is the only question like this in my textbook and i can't figure out how to solve this, i'm not the best at maths so any help people could give me would be great! The vector A = 3i + j - k is normal to the plane M1 and the vector B = 2i - j + k is normal to a...
  7. J

    finding where the two functions intersect

    im trying to find the tangets of the lines x=2sin2t and y=3sint before i can do that i need to find where they intersect. how do i find the intersection points? im lost
  8. Z

    Two sets intersect => their boundaries also intersect?

    In a topological space, if two subset A and B intersect, do their boundaries also intersect? If not, under what conditions can this statement be true? Thanks!
  9. B

    Intersect of two curves

    I really should know better but because a) I have no textbook and b) the internet was unyielding to my searches I have come to ask my question here which I really should know but it evades me. How do I find the points of intersect of the curves x^3 and x^{-3}? P.S I don't have a clue where to...
  10. Z

    Intersection Points in a Circle

    A chord is drawn between every two point on the perimeter of a circle. There are n points on the perimeter. Every two chords intersect at a point either on the perimeter or inside the circle. (a) Determine the number of chords drawn -- (n choose 2) (b) What is the maximum number of...
  11. B

    Prove that the bisectors of a triangle all intersect at the same point?

    Hi, could somebody please provide a proof on how the 3 bisectors of a triangle (lines that cut each angle in half) will, if extended fully to the other side, will pass through the same point? Obviously, two of them definitely will (because they create the point of intersection). But I need a...
  12. A

    Where does the perpendicular line intersect the ellipse again?

    I have a question which asks me to find the equation of a line perpendicular to the ellipse x^2-xy+y^2=3, at the point (-1, 1). I did this by differentiating implicitly, finding the tangent line then the line perpendicular to that. Pretty simple. The equation of the perpendicular line turned out...
  13. T

    [SOLVED] Determine if the following two lines intersect.

    Determine if the following two lines intersect. If they intersect, find the point of intersection. If they do not intersect, identify whether they are parallel, coincident or skew lines. L1: x = 1 + 2t y = -1 - t z = 3t L2: x = 1 + 3s y = 2 + 2s z = 3 + 4s Im not sure how to start this...
  14. S

    Find intersect point of tangent line to a graph

    The tangent line to the graph of y=x+ (2/x) at the point (1,3) intersects the y-axis where? I'm not sure where to start...
  15. K

    A intersect (B U C)

    I need to prove A intersect (B U C)=(A intersect B)U(A intersect C). I'm having trouble getting started....
  16. S

    Matrices: 2 lines intersect

    Okay, so here's the question: L1:[ 1 2 1 ]^T +s[ 2 -1 1 ] ^T L2: [ 3 0 1 ]^T +t[ 1 1 2 ]^T I need to find where they intersect and the cos of the acute angle theta between the lines. I was thinking of trying to put them into matrices and then trying to equate them, but I don't really know if...
  17. D

    Where the Graphs of two different equations intersect

    The Problem: I am given the graph y = sin x and 5 *\pi *y = 2x I am ask to find how many different points they intersect. I am literally blank when it comes to this question. I know solving for the system would give me one point where they intersect, but aside from graphing I have no idea as...
  18. L

    simple intersect question

    say you have y= x^2 and y = x+2 yes i know they intersect at 1,1.. its kinda easy to tell from those two functions. but i forgot how to mathmatically do this.. what formula's would u use and how would u do it.?
  19. F

    Parallel Lines intersect in Square

    Hey guys, I have an idea on how to do this problem for certain cases - does anyone know how to show this for a general case (since thats what its asking for I think): "If we have 4 points A,B,C, D which are given on a straight line (in that order), show how to construct a pair of paralllel...
  20. T

    Finding planes which intersect at a given line

    If you are given a line (r=[4,-5,6] + t[2,0,-1], how can you, from that info, figure out 3 planes which intersect at that point?