Parabola: Finding (x,y) Pairs Without Crossing Curve

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Homework Help Overview

The original poster attempts to find all pairs (x, y) in R² that do not cross a specified curve defined by the equation y = -x² + (4-2p)x + p². The problem involves understanding the relationships between points and various geometric shapes, including lines and circles, as well as the behavior of points relative to a parabola.

Discussion Character

  • Exploratory, Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants discuss the meaning of points "crossing" curves and seek clarification on the original poster's intent. There are suggestions to consider various geometric constraints, such as points lying below or above specific lines and curves, as well as inside or outside circles. Questions arise regarding the definitions of these terms and how they relate to the problem.

Discussion Status

The discussion is ongoing, with participants providing insights into the geometric interpretations of the problem. Some guidance has been offered regarding the properties of circles and parabolas, but there is no explicit consensus on how to approach the solution. Multiple interpretations of the problem are being explored.

Contextual Notes

There is a lack of clarity in the original problem statement, particularly regarding the definitions of "crossing" and the specific conditions under which pairs (x, y) are to be identified. Participants are also questioning the assumptions made about the relationships between points and the curves.

mojki1
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Find all the pairs (x, y)R^2, through which does not cross any curve : y = - x^2 + (4-2p)x + p^2 . Finding pairs (x,y) are the co-ordinate points . Thanks for help
 
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Points don't cross things...What exactly do you mean? Show us an attempt at a solution by the way, or else we can't offer any help.
 
Maybe this help
There are possible answers: Finding pairs (x,y) are the co-ordinate points
a) lyings below straight line y = -2x + 1;
b) lyings inside the circle x^2 + (y -3)^2= 9 ;
c) lyings outside the circle x^2 + (y - 3)^2 = 9;
d) lyings below the parabola y = -2 x^2 + 4x;
e) lyings on the parabola y = - x^2 + 4x;
f) lyings above parabola y = x^2 + 2x;
g) lyings below parabola y = x^2 + 2x;
h) lyings above parabola y = -2 x^2 + 4x;
i) Every point (x, y) lies on some of these curves;
j) all answers are false
I don't have any idea to solve this task.
 
What does "(x,y) lies on the graph y= f(x) mean"?

What does "above", "below", "inside", "outside" mean?
 
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Yes this points are laying on the graph y= f(x)
"inside" means that this points are in the circle or outside
below ,above the parabola.
 
Okay. Now, you know that the formula for a circle is [itex]x^2 + (y -3)^2= 9[/itex] because the are points exactly 3 units from the center point (0, 3) ([itex]x^2+ (y-3)^2[/itex] is the square of the distance from (x,y) to (0,3) and 9 is the square of 3). If a point is inside then what can you say about the distance from that point to (0,3)? What can you say about the square of that distance?

And a point is above a parabola if its y coordinate, for give x, is larger then the (x,y) on the parabola for the same x. How would you write that as an inequality?
 
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