Can You Prove This Right Triangle Theorem Involving Variables u, v, and w?

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Discussion Overview

The discussion revolves around proving a theorem related to a right triangle with legs represented by variables u and v, and hypotenuse represented by w. Participants explore the relationships between these variables given specific expressions for u and v, and aim to demonstrate the equality involving w.

Discussion Character

  • Mathematical reasoning
  • Technical explanation
  • Homework-related

Main Points Raised

  • One participant states that to show the triangle is a right triangle, it suffices to demonstrate that $$u^2 + v^2 = w^2$$.
  • Another participant clarifies that the problem does not require proving the triangle is right, as it is given, and instead focuses on manipulating the expressions for u and v to find w.
  • There is a suggestion to combine the squared expressions for u and v using a common denominator to derive w.
  • Several participants propose substituting the expressions for u and v into the equation $$w = \sqrt{u^2 + v^2}$$ to verify the required value for w.
  • One participant mentions the need to prove that the numerical value of the circumference equals the numerical value of the area, indicating a broader exploration of relationships within the triangle.

Areas of Agreement / Disagreement

Participants generally agree on the approach of using the relationship $$w^2 = u^2 + v^2$$, but there are differing opinions on the necessity of proving the triangle's right angle status, as well as the focus on circumference and area relationships. The discussion remains unresolved regarding the best method to proceed with the proof.

Contextual Notes

Some participants express uncertainty about the steps needed to combine the fractions and derive w, indicating potential limitations in the mathematical manipulations discussed.

mathdad
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A right triangle is given. The legs are u and v. The hypotenuse is w.

If u = 2(m + n)/n, and v = 4m/(m - n), show that

w = 2(m^2 + n^2)/(m - n)n

Does this question involve a^2 + b^2 = c^2?
 
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Yes, showing that:

$$u^2+v^2=w^2$$

will suffice to show that the triangle is a right triangle. :D
 
But the problem is NOT "to show that the triangle is a right triangle". We are given that the triangle is a right triangle. So we know that $$w^2= u^2+ v^2$$ and that u = 2(m + n)/n, and v = 4m/(m - n).

So [math]w^2= 4(m+ n)^2/n^2+ 16m^2/(m-n)^2[/math]

To combine those to fractions we need to get a "common denominator", [math]n^2(m-n)^2[/math]:
[math]w^2= \frac{4(m+n)^2(m-n)^2}{n^2(m-n)^2}+ \frac{16m^2n^2}{n^2(m-n)^2}[/math]

Finish that.
 
Do I square u and v to show it is equivalent to w^2?
 
From what we are given in the problem, we may state:

$$w=\sqrt{u^2+v^2}$$

Next, plug in the given values for u and v and then see if you can get to the required value for w. :D
 
MarkFL said:
From what we are given in the problem, we may state:

$$w=\sqrt{u^2+v^2}$$

Next, plug in the given values for u and v and then see if you can get to the required value for w. :D

I will definitely try this when time allows.
 
Supporting what HallsofIvy already said, we can choose to use the implicit information that $w^2=u^2+v^2$ or not.
But what we really need to do is prove that the numerical value of the circumference is the same as the numerical value of the area. Ultimately we can only do that by substituting and verifying.
 
Thank you everyone.
 

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