# Do Away With Geometric Proofs

Discussion in 'Off-Topic Chat' started by nycmathguy, Jun 28, 2022.

1. ### nycmathguy

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Is it really necessary to teach direct and indirect geometric proofs using the statement vs reason chart? What is a better, easier method for this goal?

nycmathguy, Jun 28, 2022
2. ### MathLover1

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yes, it is necessary

Direct proof employs the method of assuming the hypothesis to be true and then logically deducing that the conclusion is true using known facts.

Indirect proof whereas hangs upon the idea that assuming the conjecture to be false we lead to a contradiction which in turn leads to the case the conjecture should be true.

A two-column proof is one way to organize a proof in geometry. It is called proof table which consists of two columns. The first column contains the proof statements and the second column contains the geometric reason for those statements. Two-column proof is used in direct proof.

MathLover1, Jun 28, 2022
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3. ### nycmathguy

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I never understood the two-column proof. If the two-column method is used for direct proofs, what method is used for indirect proofs? Are you good at answering direct and indirect geometric proofs? If so, I would like your help with this material. The same applies to bearings in trigonometry.

nycmathguy, Jun 28, 2022
4. ### MathLover1

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sure
There are two methods of indirect proof: proof of the contrapositive and proof by contradiction. They are closely related, even interchangeable in some circumstances, though proof by contradiction is more powerful. What unites them is that they both start by assuming the denial of the conclusion.

MathLover1, Jun 28, 2022
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5. ### nycmathguy

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I had no idea that you know how to do direct and indirect geometric Proofs. I definitely will need a helping hand in this department. I will also need you to help with me with geometric construction problems and bearing problems in trigonometry.

nycmathguy, Jun 29, 2022