{"id":8959,"date":"2020-12-04T09:42:40","date_gmt":"2020-12-04T04:12:40","guid":{"rendered":"https:\/\/cbselibrary.com\/?p=8959"},"modified":"2020-12-04T12:55:59","modified_gmt":"2020-12-04T07:25:59","slug":"proof","status":"publish","type":"post","link":"https:\/\/cbselibrary.com\/proof\/","title":{"rendered":"What is a Proof"},"content":{"rendered":"
A proof<\/strong> is a written account of the complete thought process that is used to reach a conclusion. Each step of the process is supported by a theorem, postulate or definition verifying why the step is possible. If you think about the numerical problems you are used to solving in geometry, you will realize that your mind often does a “fast-forward” through some of the logical steps needed to reach a valid answer. In other words, you quickly “go right to the answer.” When developing a proof of this same problem, we must be careful to include ALL of the steps that led to our answer. We cannot “fast-forward” over steps when writing a proof. Check out the “proof” of this same problem: What’s in a proof? A Successful Strategy:\u00a0<\/strong>Backwards Looking<\/strong><\/p>\n For most proof problems, it is very helpful to examine the problem backwards — from the “Prove” statement back to the “Given” information. Let’s look at an example: What is a Proof A proof is a written account of the complete thought process that is used to reach a conclusion. Each step of the process is supported by a theorem, postulate or definition verifying why the step is possible. In formal Euclidean proofs, no steps can be left out. If you think about … Read more<\/a><\/p>\n","protected":false},"author":8,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"spay_email":""},"categories":[5],"tags":[3275],"yoast_head":"\n
\nIn formal Euclidean proofs, no steps can be left out.<\/p>\n
\nCheck out the numerical problem below:
\nYou probably arrived at the answer of 6 long before you finished reading the explanation of the answer. Right?<\/p>\n
\nA proof requires that you document all of the little steps that you mentally “fast-forwarded” through in the numerical problem.<\/p>\n
\nA formal 2-column proof contains the following components:<\/p>\n\n
\nExample:<\/strong>
\n
\nThis information is usually stated in the original problem. \u00a0Some word problems, however, have to be dissected in order to get the specific information needed for the proof.<\/li>\n
\nExample:<\/strong>
\n
\nThe diagram usually is not marked, so this step is very important. You will see the sought after congruent triangles and their corresponding parts much clearer with the diagram marked.<\/li>\n
\nExample:
\n<\/strong>\\(\\overline { AD }\\) \u2245 \\(\\overline { AB }\\), \u22211\u2245 \u22212
\nStating of the “given” information is almost always the first statement, and the reason is simply GIVEN.<\/li>\n
\nExample:<\/strong>
\n1. Given
\n2. Reflexive Property
\n3. SAS: If 2 sides and the include angle one triangle are congruent respectively to 2 sides and the included angles of a second triangle, then the 2 triangles are congruent.
\n4. Corresponding parts of congruent triangles are congruent.
\nThese supporting “reasons” vary between textbooks (and teachers), so be careful to follow the guidelines set by your teacher.<\/li>\n
\nExample:
\n<\/strong>\\(\\overline { CD }\\) \u2245 \\(\\overline { CB }\\)
\nThe “PROVE” is always the final statement. This statement is the purpose for the entire problem.<\/li>\n<\/ul>\n
\n
\nA Backwards Look — Where does the conclusion come from?
\n
\nBy looking at the above steps, we can see how to proceed with the proof. You might want to consider jotting down your “backward” thoughts before you begin writing your proof.
\n<\/p>\n","protected":false},"excerpt":{"rendered":"