What does the equation xy=k represent?

  • Thread starter Thread starter svigneshkumars
  • Start date Start date
AI Thread Summary
The equation xy=k represents a relationship where x and y are variables, and k is a constant. This can be interpreted as a function f(x, y) = k, where the output is the product of the inputs x and y. When solved for y, it reveals an inverse variation, expressed as y = k/x. The graphical representation of this equation is a hyperbola, indicating that as one variable increases, the other decreases. Overall, the interpretation of the equation can vary based on the context of the variables involved.
svigneshkumars
Messages
10
Reaction score
0
What does the eqn xy=k represent?
 
Mathematics news on Phys.org


It depends upon the interpretation of your symbols x,y and k.
 


In many cases, that will represent a function (though I'm used to seeing z insteak of k.)
f(x, y) = k. In your case, f(x, y) takes the two inputs (x and y, obviously) and multiplies them together. k is called the output, x and y are inputs. Most people will remember seeing f(x) = y in high school, in this case f() has two variables intead of one. As Arlidno mentions, the interpretation will vary. x may represent height and y may represent width, hence k would represent the area of a square-ish object.
 


svigneshkumars said:
What does the eqn xy=k represent?

Well, if you solve it for y, then you get: y = k/x. This is an inverse variation.

It could be as simple as that.
 


Assuming x and y are variables and k is a constant, the graph will be a hyperbola.
 


Assuming "xy" is a constant, the k-graph is either a straight line, assuming a (k,l)-coordinate system to speak out from.
 
Seemingly by some mathematical coincidence, a hexagon of sides 2,2,7,7, 11, and 11 can be inscribed in a circle of radius 7. The other day I saw a math problem on line, which they said came from a Polish Olympiad, where you compute the length x of the 3rd side which is the same as the radius, so that the sides of length 2,x, and 11 are inscribed on the arc of a semi-circle. The law of cosines applied twice gives the answer for x of exactly 7, but the arithmetic is so complex that the...
Is it possible to arrange six pencils such that each one touches the other five? If so, how? This is an adaption of a Martin Gardner puzzle only I changed it from cigarettes to pencils and left out the clues because PF folks don’t need clues. From the book “My Best Mathematical and Logic Puzzles”. Dover, 1994.
Back
Top