Cartesian Definition and 561 Threads

In mathematics, specifically set theory, the Cartesian product of two sets A and B, denoted A × B, is the set of all ordered pairs (a, b) where a is in A and b is in B. In terms of set-builder notation, that is




A
×
B
=
{
(
a
,
b
)

a

A



and



b

B
}
.


{\displaystyle A\times B=\{(a,b)\mid a\in A\ {\mbox{ and }}\ b\in B\}.}
A table can be created by taking the Cartesian product of a set of rows and a set of columns. If the Cartesian product rows × columns is taken, the cells of the table contain ordered pairs of the form (row value, column value).One can similarly define the Cartesian product of n sets, also known as an n-fold Cartesian product, which can be represented by an n-dimensional array, where each element is an n-tuple. An ordered pair is a 2-tuple or couple. More generally still, one can define the Cartesian product of an indexed family of sets.
The Cartesian product is named after René Descartes, whose formulation of analytic geometry gave rise to the concept, which is further generalized in terms of direct product.

View More On Wikipedia.org
  1. C

    Cartesian unit vectors expressed by Cylindrical unit vectors

    please someone explain me the following expression for Cartesian unit vectors expressed by the cylindrical unit vectors: http://web.mit.edu/8.02t/www/materials/modules/ReviewB.pdf at page B-8 line B.2.4 i would like to know which steps led to it. thanks, Chen
  2. W

    An alpha particle is at rest at the origin of a Cartesian coordinate system

    Homework Statement An alpha particle (the nucleus of a helium atom) is at rest at the origin of a Cartesian coordinate system. A proton is moving with a velocity of v towards the alpha particle in the xˆ direction. If the proton is initially far enough away to have no potential energy, how...
  3. Ascendant78

    Mechanics in cartesian coordinates

    Homework Statement A cannon shoots a ball at an angle θ above the horizontal ground. (a) Neglecting air resistance, use Newton's second law to find the ball's position as a function of time. (Use axes with x measured horizontally and y vertically.) (b) Let r(t) denote the ball's distance...
  4. L

    Vector Multiplication in a Triangle on the Cartesian Plane

    Homework Statement For the vectors in a Triangle, with a = 16, b = 12, and c = 20 what are (a) the magnitude and (b) the direction of A x B (c) the magnitude and (d) the direction of A x C (e) the magnitude and (f) the direction B x C this is Vector Multiplication. Homework Equations...
  5. davidbenari

    How to prove gradients vectors are the same in polar and cartesian co.

    Suppose T=T(r,θ)=G(x,y) How do you prove ∇T(r,θ)=∇G(x,y)? I can think of some arguments in favor of this equality, but I want an actual proof or a very good intuitive argument. My arguments in favor go something like this: -Gradient vectors should be the same because if my directional...
  6. Greg Bernhardt

    What is Cartesian Coordinates & Formulas?

    Definition/Summary Cartesian coordinates are ordinary rectangular coordinates in a flat Euclidean space. Cartesian form of a complex number is the form x + iy, where x and y are real. Cartesian product of two or more sets is the most general product set, the direct product, with the symbol...
  7. O

    Why do some heats of matches go down first in a Cartesian diver experiment?

    Hello. I think that you know an experiment called Cartesian diver. I can use some heads of matches like Castesian divers like there: I know how it works. However, I don't know why the heats of matches don't go down in some moment, but first one, then second with bigger force, then third with...
  8. T

    What Does an Isotropic Cartesian Tensor Look Like in Higher Dimensions?

    Does anyone have a proof of what a isotropic cartesian tensor should look like in three or four dimensions?
  9. C

    Cartesian or Polar Coordinates to store intergalactic objects in DB?

    So I'm wondering, should I use Cartesian or Polar Coordinates to store intergalactic objects in DB? I'm currently prototyping a game idea that can be oversimplified as a spaceship simulator in infinite space. I'm considering grouping objects together so that they have a "parent super-space"...
  10. T

    Finding cartesian equation of plane

    Homework Statement determine the Cartesian equation of the plane through the points (3,0,1) and (0,1,-1) and perpendicular to the plane with equation x-y-z+1 = 0 Homework Equations The Attempt at a Solution Well I know the normal of the plane (a,b,c) dotted with (1,-1,-1) = 0...
  11. paulmdrdo1

    MHB Help with Vector Questions in a Cartesian Coordinate System

    I'm not sure if it is the right place to post my questions to. please let me know if this should be somewhere else. 1. let each of the vectors $A=5a_x-a_y+3a_z$ $B=-2a_x+2_ay+4a_z$ $C=3a_y-4a_z$ extend outward from the origin of the cartesian coordinate system to points A,B, And...
  12. Feodalherren

    From Cartesian to spherical integral

    Homework Statement Homework Equations The Attempt at a Solution Is this the correct setup? \int^{\pi}_{\frac{3\pi}{4}}\int^{2\pi}_{0}\int^{\sqrt{2}}_{0}\frac{1}{\rho^{2}} rho^2 Sin\phi d\rho d\theta d\phi I gave up on itex. It was either that or my computer flying out the...
  13. D

    Cartesian product of (possible infinite) family of sets

    Hi all. I'm having trouble understanding the cartesian product of a (possible infinite) family of sets. Lets say \mathcal{F} = \{A_i\}_{i \in I} is a family of sets. According to wikipedia, the cartesian product of this family is the set \prod_{i \in I} A_i = \{ f : I \to \bigcup_{i...
  14. N

    Cartesian to polar confusion (simple)?

    Homework Statement Convert -2+2√3i to polar coordinates. Homework Equations r = √x2+y2 θ = tan-1(y/x) The Attempt at a Solution I am confused because θ = tan-1(2√3/2) = tan-1(√3) = -π/3 and r = 4, so that would make the polar form 4cis(-π/3), but the calculator gives: 4cis(2π/3). I...
  15. C

    Cartesian product of index family of sets

    Cartesian product of indexed family of sets The definition of a Cartesian product of an indexed family of sets (X_i)_{i\in I} is \Pi_{i\in I}X_i=\left\{f:I \rightarrow \bigcup_{i \in I} \right\} So if I understand correctly, it's a function that maps every index i to an element f(i) such...
  16. F

    Why Does Gauss's Law Give Zero Flux for a Point Charge in Cartesian Coordinates?

    I'm running through the following problem in an EM text of mine: Calculate the flux of a point charge Q at the origin through a cube centered through the origin by both direct integration and Gauss's Law (essentially prove Gauss's Law for a point charge). Now I got the answer of Q/ε0 via...
  17. C

    Power sets and Cartesian products.

    Homework Statement For every pair of sets (A,B) we have P(AxB)=P(A)xP(B) Prove or disprove the above statement. Homework Equations The Attempt at a Solution I have attempted solving this using A={1,2} and B={a,b} AxB={(1,a),(1,b),(2,a),(2,b)}...
  18. V

    Mathematical connection in the cartesian product

    mathematical "connection" in the cartesian product What is the mathematical connection between elements of a cartesian product ##A\times{}B## and the elements of the sets ##A## and ##B##? In other words, what is the difference between the set ##A\times{}B## and just any set ##Z## with...
  19. A

    MHB How Do You Solve This Cartesian Geometry Problem?

    Hello I've got a problem with Cartesian Geometry and cannot find a solution. A will appretiate any help I can get. b) Show that [AQ] has equation cx + by = -2ac c) Prove that the third median [BR] passes through the point of intersection G of medians [OP] and [AQ] Cheers!
  20. 7

    Projected component of F along a line in cartesian question.

    Homework Statement Determine the magnitude of the projected component of F along AC. Express this component as a Cartesian vector.Homework Equations Information I'm working with. The Attempt at a Solution Most of my attempts have proven fruitless. I understand that in order to find a...
  21. J

    Pneumatic valve for cartesian robot

    Hello, I am trying to build a high-speed X/Y cartesian robot which vacuums up defected parts from a moving conveyor. The end effector of the robot has a venturi vacuum integrated. Because the vacuum is constant, I need a Z-axis to go up/down for the end effector to get the defects otherwise...
  22. M

    Transformation of the metric tensor from polar to cartesian coords

    I'm working on a problem that requires me to take the cartesian metric in 2D [1 0;0 1] and convert (using the transformation equations b/w polar and cartesian coords) it to the polar metric. I have done this without issue using the partial derivatives of the transformation equations and have...
  23. J

    Vectorial kinematic in cartesian and polar system/notanion

    I was trying to study vectorial kinematics in all its fullness, without decorating formulas, only deducting all vectorially through mathematical definitions. I felt much difficulty, because it's a puzzle of many pieces and I not found a embracing explanation in any book. Someone could explain to...
  24. I

    Algebraically Revising the Angle Between Two Vectors in 2-D Cartesian Space

    I am revising vectors at the moment. So, this is not a homework question. In 2-D cartesian space, I have two vectors, A = <a,2> and B = <1,3>. I want to find the limit of the angle between the vectors as a -> -∞. Geometrically, I know that direction of vector B approaches 180° as a→-∞...
  25. I

    Double integral: Cartesian to Polar coordinates

    Homework Statement ∫∫√(x^2+y^2)dxdy with 0<=y<=1 and -SQRT(y-y^2)<=x<=0 Homework Equations x=rcos(theta) y=rsin(theta) The Attempt at a Solution 0.5<=r=1, we get r=0.5 from -SQRT(y-y^2)<=x by completing the square on the LHS then, 0<=theta<=pi But, when I calculated the...
  26. P

    Cartesian Product of Permutations?

    Suppose I was asked if G \cong H \times G/H . At first I considered a familiar group, G = S_3 with its subgroup H = A_3 . I know that the quotient group is the cosets of H, but then I realized that I have no idea how to interpret a Cartesian product of any type of set with elements that aren't...
  27. skate_nerd

    MHB Showing relationship between cartesian and spherical unit vectors

    I am asked to show that when \(\hat{e_r}\), \(\hat{e_\theta}\), and \(\hat{e_\phi}\) are unit vectors in spherical coordinates, that the cartesian unit vectors $$\hat{i} = \sin{\phi}\cos{\theta}\hat{e_r} + \cos{\phi}\cos{\theta}\hat{e_\phi} - \sin{\theta}\hat{e_\theta}$$ $$\hat{j} =...
  28. L

    Curl in spherical coords with seeming cartesian unit vector

    Homework Statement I have a problem that is the curl of jln(rsinθ) Since this is in spherical, why is there a bold j in the problem? Doesn't that indicate it's a unit vector in cartesian coordinates? Can I do the curl in spherical coordinates when I have a cartesian unit vector in the...
  29. N

    MHB Converting from Cartesian to polar form

    another question: convert $|\frac{1-i}{3}|$ to polar form i am getting $\frac{\sqrt{2}}{3} e^{\frac{i\pi}{4}}$ but the solutions say: $e^{\frac{-i\pi}{4}}$ i did $ x = r\cos(\theta)$ and $y=r\sin(\theta)$ so $\frac{1}{3} = {\frac{\sqrt{2}}{3}}\cos(\theta)$ $\frac{1}{3} = \cos(\theta)$ And...
  30. 2

    Comp Sci [fortran90] cartesian to polar coordinate

    Write a short FORTRAN90 subroutine to convert Cartesian coordinates (x, y, z) to spherical polar coordinates (r, q, f) using • Write a FORTRAN90 program which uses this subroutine to convert the following (x, y, z) coordinates which are read from a text file and stored within a single vector...
  31. J

    Lagrangian in cartesian and polar

    Homework Statement Consider the following Lagrangian in Cartesian coordinates: L(x, y, x', y') = 12 (x^ 2 + y^2) -sqrt(x^2 + y^2) (a) Write the Lagrange equations of motion, and show that x = cos(t); y =sin(t) is a solution. (b) Changing from Cartesian to polar coordinates, x = r...
  32. stripes

    Calculating the characteristic of the cartesian product of rings

    Homework Statement See attached image Homework Equations The Attempt at a Solution For the first half of the question, ordered pairs would be (1, [1]), since 1 and [1] are the multiplicative identities in these rings. but no matter how many times we add (1, [1]) to itself...
  33. D

    Cartesian Product of two sets?

    Homework Statement I need to answer a bunch of topological questions based on the cartesian product of two sets, but I'm not entirely sure how to graph them out. I have A = [1,2)U{3} and B = {1, (1/2), (1/3), ...}U[-2,-1). S = A x B, and I need the graph of S. Could anyone help me with...
  34. PeteyCoco

    Line integral of a spherical vector field over cartesian path

    Homework Statement Compute the line integral of \vec{v} = (rcos^{2}\theta)\widehat{r} - (rcos\theta sin\theta)\widehat{\theta} + 3r\widehat{\phi} over the line from (0,1,0) to (0,1,2) (in Cartesian coordinates) The Attempt at a Solution Well, I expressed the path as a...
  35. A

    Calculating elliptic orbits in Cartesian coordinates

    I have a function to plot the orbits of planets based on their orbital elements (Semi-major Axis, Eccentricity, Argument of periapsis, Inclination, and longitude of ascending node). I have the x and y coordinates working great using only the semi-major axis, eccentricity, and argument of...
  36. A

    Convert unit vector from cartesian to spherical coordination

    i have a problem : A small loop antenna in free space and centered about the origin on the xy-plane is producing a (far-field) radiation electric field (in phasor notation) : http://postimg.org/image/63tm76h5l/ and their solution : http://postimg.org/image/6mdm6roh9/ i don't understand how...
  37. L

    How to rotate Cartesian coordinate system?

    Hello, I would like to rotate the Cartesian coordinate system ( i=(1,0,0); j=(0,1,0); k=(0,0,1) ) so that angles between new and the old axes be equal to α, β and γ, respectively. Is any simple way similar to the Euler transformations to accomplish that?
  38. P

    Cylindrical continuity eq using cartesian substitution.

    I've have two questions, but if my assumption is incorrect for the first, it will also be incorrect for the second. (in-terms of physics.) For a two dimensional cylinder, using cylindrical co-ordinates (as follows), taking v(subscript-r) => velocity normal to cylinder surface & v(subscript-phi)...
  39. E

    A cylinder rotating in Cartesian coordinate system

    Homework Statement In Cartesian coordinaate system, we describe the rotation of a cylinder. The axis of the cylinder has the same direction as the basis vector e3. Angular velocity is described by vector w = 2e1 - 5e2 + 7e3 rad/s. I must find the velocity vector (v) of a point P that is...
  40. I

    Help with a cartesian problem to find a geocache.

    okay first hello. i hope someone can help me with this. i am working on a mystery geocache that the hint says is a cartesian problem. i will copy the info below and add a link to the page if you want to look at it. again thanks for any help...
  41. R

    Statics: Forces in Cartesian Vector form

    Homework Statement For cable AD it is known that the magnitude is 14 kips, x-component has a value of -6.216, the direction angle in the z-direction is 83.63°, and Fy is less than zero. Find forces in Cartesian vector form, coordinates of point D if it lies on the x-z plane and point A is (0...
  42. T

    Defining geometry within a cartesian coordinate system

    Hello, Just as a warning before anyone reads my question I am not a mathematician, just an engineer with moderate math skills he wants to expand. So I'm writing some engineering software which involves defining/interation/modification of geometry within a cartesian system but I currently...
  43. W

    How can I solve for beta and gamma in a cartesian vector addition problem?

    I am having a really tough time trying to solve this particular problem I can find alpha easily 139 degrees which is correct. However when I go to try and solve for beta or gamma I get this huge mess and I am unable to solve for either one, Please help me I know I am overlooking something but I...
  44. W

    Convert vector-field from cylindrical to cartesian

    Homework Statement I have a vector field (which happens to be a magnetic field) H = -\frac{I }{2 \pi r}u\varphi u\varphi is the unit vector which is in the cylindrical coordinate system with only the \varphi component nonzero so it circles around the z-axis. r is the radius of the circle...
  45. R

    Cartesian Distance from Origin in the XY Plane

    1. The cartesian coordinates of a point in the xy plane are x=−9.92 m, y=−2.8 m.Find the distance "r" from the point to the origin.Answer in units of m Homework Equations A=sqrt(Axi^2 + Ayj^2) The Attempt at a Solution i did the following: A=sqrt((-9.92m)^2 + (-2.8m)^2) and got...
  46. M

    Can a 2nd degree parametric equation be turned into cartesian?

    Let's say i have a parametric equation: x = t^2 y = t^3 + 4t Even though this is a 2nd and 3rd degree parametric equation, i can isolate and express in terms of y = f(x) because the parametric equation for x involves only one term for t. Thus: t = sqrt(x) and y = sqrt(x)^3 + 4(sqrt(x))...
  47. D

    Converting from cartesian to spherical boundaries

    If I had a sphere centred at the origin with x > 0, y > 0 and z > 0 Would the angle boundaries be: 0 < θ < pi/2 0 < α < pi/2 ?
  48. S

    How to translate from polar to cartesian coordinates:

    How to translate r = 2 /(2 - cos(theta)) to cartesian coordinates: so far: r = 2 /(2 - cos(theta)) r = 2 /(2 - cos(theta)) |* (2 - cos(theta)) both sides r (2 - cos(theta))= 2 2*r - rcos(theta) = 2 | know x = rcos(theta) 2*r - x...
  49. H

    The Cartesian product theorem for dimension 0

    The cartesian product ∏X = Xi of a countable family {Xi} of regular spaces is zero-dimensional i f and only i f all spaces Xi , are zero-dimensional. I wonder if the countability assumption is just to ensure the regularity of the product space ,or it is crucial for the clopen basis. Thank's
  50. J

    Cartesian and vector equations

    Homework Statement The position vectors of two points a and b on a line are < 2,1,7> and < 1,4,-1> Find the parametric vector equation for any point on the line. Find the linear Cartesian equation of the line using x, y, z as coordinates. Homework Equations For the parametric eq. x...
Back
Top