Solving the Multivariable Proof: A+C/B+D < E+G/F+H

  • Context: Graduate 
  • Thread starter Thread starter Fenix
  • Start date Start date
  • Tags Tags
    Multivariable Proofs
Click For Summary
SUMMARY

The discussion centers on the mathematical inequality involving eight integer variables: A, B, C, D, E, F, G, and H. The inequalities A/B > E/F and C/D > G/H are established, leading to the question of whether (A+C)/(B+D) can be less than (E+G)/(F+H). The user presents specific examples, including A=1, B=2, C=1, D=2, E=-200, F=50, G=150, and H=-100, which demonstrate that the inequality can hold true. The conversation seeks methods to derive parameters for the variables that satisfy the inequality.

PREREQUISITES
  • Understanding of basic algebraic inequalities
  • Familiarity with integer variables and their properties
  • Knowledge of mathematical proofs and counterexamples
  • Experience with manipulating fractions and ratios
NEXT STEPS
  • Explore advanced techniques in algebraic manipulation
  • Study mathematical proofs involving inequalities
  • Investigate integer programming methods for variable optimization
  • Learn about the properties of rational functions and their limits
USEFUL FOR

Mathematicians, students studying algebra, and anyone interested in solving complex inequalities involving multiple variables.

Fenix
Messages
9
Reaction score
0
I'm confronted with the following question that may of may not have a solution:

You are given eight variables, A, B, C, D, E, F, G, and H.

These variables are integers.

You know that:

A/B > E/F

and

C/D > G/H

Is it possible that (A+C)/(B+D) < (E+G)/(F+H)?

I've tried everything, such as multiplying, and expanding, but that did not get me anywhere. I also tried trial and error with unsuccessful results.

Is it even possible?
 
Mathematics news on Phys.org
how about C=D=10000000000, G=1,H=2,A=1000,B=1,E=500,F=1
 
That's so astronomically huge!

I was thinking about it, and found another solution:

A=1
B=2
C=1
D=2
E=-200
F=50
G=150
H=-100

1/2 < -50/-50 = 1

Now that we found some variables that solved the existence of the question, how can we begin to apporach at deriving the parameters of the variables that will satisfy A+C/B+D < E+G/F+H?
 

Similar threads

  • · Replies 2 ·
Replies
2
Views
1K
  • · Replies 21 ·
Replies
21
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 2 ·
Replies
2
Views
1K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 20 ·
Replies
20
Views
2K
Replies
1
Views
2K
  • · Replies 4 ·
Replies
4
Views
1K