Proving No Common Solution for Equations (1) and (2)

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In summary, "proving no common solution" means demonstrating that there is no solution that satisfies all given equations or statements. It is important because it allows us to identify inconsistencies and avoid making incorrect assumptions. This can be done using mathematical techniques and critical thinking skills. However, there can be exceptions in certain scenarios where multiple solutions are all valid, but there is no one solution that satisfies them all. "Proving no common solution" also has real-world applications in fields such as mathematics, physics, and engineering, helping to improve the accuracy of predictions and solutions.
  • #1
Albert1
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$ assume \,\, a>2\,\, and \,\, b>2$
$x^2-abx+(a+b)=0---(1)$
$x^2-(a+b)x+ab=0---(2)$
$prove \,\, (1)\,\, and \,\, (2)\,\, have \,\, no\,\ common \,\, solution$
 
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  • #2
Looks straightforward. If there exist a number, x, such that
$x^2- abx+ (a+ b)= 0$ and
$x^2- (a+ b)x+ ab= 0$

then, subtracting, $(a- ab+ b)x+ (a- ab+ b)= 0$ which has the single solution $x= -1$. Putting $x= -1$ into both equations, $1+ ab+ a+ b= 0$ and $1+ a+ b+ ab= 0$. Since a and b are both positive numbers, that is impossible.
 
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  • #3
HallsofIvy said:
Looks straightforward. If there exist a number, x, such that
$x^2- abx+ (a+ b)= 0$ and
$x^2- (a+ b)x+ ab= 0$

then, subtracting, $(a- ab+ b)x+ (a- ab+ b)= 0$ which has the single solution $x= -1$. Putting $x= -1$ into both equations, $1+ ab+ a+ b= 0$ and $1+ a+ b+ ab= 0$. Since a and b are both positive numbers, that is impossible.

One part was overlooked that a+b - ab = 0 or (a-1)(b-1) =1 this is pssible for positive a, b ( for example a = 1.5, b= 3) but not for given condition and b both greater than 2 as both terms are geater han 1 so the product.
 

FAQ: Proving No Common Solution for Equations (1) and (2)

What does it mean to "prove no common solution"?

Proving no common solution means showing that there is no solution that satisfies all the given equations or statements. This is often used in mathematics to show that a set of equations or statements is inconsistent.

Why is it important to prove no common solution?

Proving no common solution is important because it allows us to identify inconsistencies in our equations or statements. It can also help us avoid making incorrect assumptions or conclusions based on faulty data or reasoning.

How can I prove no common solution?

Proving no common solution often involves using mathematical techniques such as substitution, elimination, or contradiction. It may also require logical reasoning and critical thinking skills.

Can there ever be exceptions to "proving no common solution"?

Yes, there can be exceptions to "proving no common solution" in certain scenarios. For example, some equations or statements may have multiple solutions that are all valid, but there is no one solution that satisfies them all simultaneously.

Are there any real-world applications for "proving no common solution"?

Yes, "proving no common solution" has real-world applications in fields such as mathematics, physics, and engineering. It can help identify inconsistencies in data or models, which can lead to more accurate predictions and solutions.

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