MHB When Are the Equivalence and Inequality Met?

  • Thread starter Thread starter Albert1
  • Start date Start date
AI Thread Summary
The discussion centers on proving the inequality EF + FG + GH + HE ≥ 2AC for rectangle ABCD with points E, F, G, and H on its sides. It is established that the equality holds when points E, F, G, and H are the midpoints of the respective sides of the rectangle. The proof involves rearranging segments to demonstrate that the total length of EF, FG, GH, and HE is at least twice the length of the diagonal AC. Additionally, the relationship between the segments and the diagonals is illustrated through geometric figures. The equivalence is achieved specifically when the points are positioned at the midpoints of the rectangle's sides.
Albert1
Messages
1,221
Reaction score
0
Rectangle ABCD ,having fours points$ E,F,G,H $ located on segments AB, BC, CD,and

DA respectively , please prove :

$EF+FG+GH+HE\geq 2 AC $

and determine when the equivalence can be taken ?
 
Mathematics news on Phys.org
Re: Ef+fg+gh+he>=2ac

suppose we have another three cards equivalent to figure 1 ,and rearranging these four cards
in a position as shown in figure 2
from figure 2 we see :2AC=AP=HQ< HG+GM+MN+NQ=EF+FG+GH+HE
figure 3 shows the equivalence will be taken when E,F,G,H are midpoints of AB,BC,CD,and DA respectively
2AC=AC+BD=EF+FG+GH+HE
View attachment 1644
 

Attachments

  • rectangle.jpg
    rectangle.jpg
    31.6 KB · Views: 75
Suppose ,instead of the usual x,y coordinate system with an I basis vector along the x -axis and a corresponding j basis vector along the y-axis we instead have a different pair of basis vectors ,call them e and f along their respective axes. I have seen that this is an important subject in maths My question is what physical applications does such a model apply to? I am asking here because I have devoted quite a lot of time in the past to understanding convectors and the dual...
Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. In Dirac’s Principles of Quantum Mechanics published in 1930 he introduced a “convenient notation” he referred to as a “delta function” which he treated as a continuum analog to the discrete Kronecker delta. The Kronecker delta is simply the indexed components of the identity operator in matrix algebra Source: https://www.physicsforums.com/insights/what-exactly-is-diracs-delta-function/ by...
Back
Top