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In mathematics and logic, a direct proof is a way of showing the truth or falsehood of a given statement by a straightforward combination of established facts, usually existing lemmas and theorems, without making any further assumptions. In order to directly prove a conditional statement of the form "If p, then q", it is only necessary to consider situations where the statement p is true. Logical deduction is employed to reason from assumptions to conclusion. The type of logic employed is almost invariably first-order logic, employing the quantifiers for all and there exists. Common proof rules used are modus ponens and universal instantiation. In contrast, an indirect proof may begin with certain hypothetical scenarios and then proceed to eliminate the uncertainties in each of these scenarios until an inescapable conclusion is forced. For example instead of showing directly p → q, one proves its contrapositive ~q → ~p (one assumes ~q and shows that it leads to ~p). Since p → q and ~q → ~p are equivalent by the principle of transposition, one has indirectly proved p → q. Proof methods that are not direct include Proof by contradiction. Direct proof methods include Proof by exhaustion, Proof by infinite descent and Proof by induction. From Wikipedia under the
GNU Free Documentation License  goodmyx.com 165px x 147px | 3.70kB [source page] Parent Directory 24 Jul 2008 20 08 nikwax s jpg 13 Apr 2008 16 58 3k tent gear proof jpg 13 Apr 2008 16 58 4k tx direct spray jpg 13 Apr 2008 16 58 4k  images.spaceref.com 142px x 202px | 24.40kB [source page] NASA Finds Direct Proof of Dark Matter Monday August 21 2006 Dark matter and normal matter have been wrenched apart by the tremendous collision of two large clusters of galaxies The From Yahoo Image Search: "Direct proof"  atheistwatch.blogspot.com J.L. Hinman Sun, 04 Oct 2009 23:15:00 GM You are trying to say that science is the only form of knowledge so therefore anything that is scientific is automatically redeemed from not having . direct proof. . But an idea that is not a scientific idea, if not proved directly must be ...  forum.flyff.musara-network.net Anuimx Sun, 03 Jan 2010 07:45:29 GM Im sorry if you lost any items from the rollback, but they will unfortunatly not be restored unless you have . direct proof. of it, but honestly even with pictures, its not good enough, so just go on with your life. lol. ...  juancarlosiza.blogspot.com Juan Carlos Iza Mon, 04 Jan 2010 00:25:00 GM Finally the judge didn't sentence David because there weren't enough tests, a . direct proof. but the court recommended that David was 100 in juvenile detention. Thirty- four days later David returned to Lillian's house. From Google Blog Search: "Direct proof"  news.google.com Chicago Tribune To get there herself, Jackson is selling her own narrative of growing up in a family without work and health care as proof that she best understands the ... and more » news.google.com CoinLink The United States Mint also produces proof , uncirculated and commemorative coins; Congressional Gold Medals; and silver, gold and platinum bullion coins. and more » news.google.com Deadspin (blog) But it never pays to take chances, and now you can buy stab- proof body armor emblazoned with your country's flag. Enter the Protektor Vest. ... and more » From Google News Search: "Direct proof" the question is consider the statement: if a/b and b/c then a/c. Give a direct proof? Q. the question is consider the statement: if a/b and b/c then a/c. Give a direct proof? Asked by jutsu - Wed Jan 17 03:06:33 2007 - - 4 Answers - 0 Comments A. if a = b and b=c, then a has to be the same as c. i.e. a = b = c Answered by Kinu Sharma - Wed Jan 17 03:14:16 2007 What is the most ancient proof of human life you know? Q. Please, direct us to the proof or indication, thank you! Asked by soubassakis - Wed Nov 15 13:28:07 2006 - - 4 Answers - 0 Comments A. Hello dear! I was fortunate to visit the cave of Petralona, Chalkidiki, North Greece. From the cave and around it, there are many findings proving the existence of intelligent life, human! First, skull and bones that are more than a million year old, which belong to standing human being. Also, there are control fire places, dated more than 4 million years old, with food, bones etc. and the fire was protected by circles of stones. Also, among the findings from North Greece to Crete, Greece, are tools dated more than 13 million years ago. You can search at: www.aee.gr Answered by cosmos - Fri Nov 17 18:36:50 2006 Please arrange direct T.V. telecast and provide proof to Pakistan for this terrorist attack on Mumbai - A LIVE?
Q. To put press on Government for this tragedy took place in Mumbai, get help of media personnel as India is very big country and we don t have time to go door to door and ask peoples or open their eyes as we all are habitual of this all I called it as sickness of forgetfulness . Please arrange direct T.V. telecast and call foreign minister Mr.Qureshi of Pakistan who informed that Pakistan will take action against any group if India gives PROOF . Please call all important Government officials in a live interview and make arrangement to have live interview in front of arrested terrorists Ajmal Mohammed Amir Kasab , resident of Faridkot village in Pakistani Punjab s Ukada district If this live interview is arranged I believe there will no… [cont.] Asked by pankaj s - Tue Dec 2 02:37:48 2008 - - 4 Answers - 0 Comments A. Which proof you are asking. Entire world knows. Pakistan is the school of terrorism. BBC, cnn and all leading news channels around the world live telecasting this worst terrorist attack on Mumbai. But you still need proof. Pakistan always divert the attention of the people of the world by asking proof. Daily 100's of Indians killed by terrorist. But Indian government should not take any action against Pakistan. Vote Bank Politics completely spoiled our country. The only solution left for our public is "Stay in Your house, don't go to office, children don't go to school. Stay in your house is the only option left now with our people. Because these politicians never take bold action against Pakistan. Pakistan is the one of the smallest… [cont.] Answered by Ranga N - Tue Dec 2 20:06:52 2008 From Yahoo Answer Search: "Direct proof" |
