Search the forum,

proof

A mathematical proof is an inferential argument for a mathematical statement, showing that the stated assumptions logically guarantee the conclusion. The argument may use other previously established statements, such as theorems; but every proof can, in principle, be constructed using only certain basic or original assumptions known as axioms, along with the accepted rules of inference. Proofs are examples of exhaustive deductive reasoning which establish logical certainty, to be distinguished from empirical arguments or non-exhaustive inductive reasoning which establish "reasonable expectation". Presenting many cases in which the statement holds is not enough for a proof, which must demonstrate that the statement is true in all possible cases. An proposition that has not been proved but is believed to be true is known as a conjecture, or a hypothesis if frequently used as an assumption for further mathematical work.
Proofs employ logic expressed in mathematical symbols, along with natural language which usually admits some ambiguity. In most mathematical literature, proofs are written in terms of rigorous informal logic. Purely formal proofs, written fully in symbolic language without the involvement of natural language, are considered in proof theory. The distinction between formal and informal proofs has led to much examination of current and historical mathematical practice, quasi-empiricism in mathematics, and so-called folk mathematics, oral traditions in the mainstream mathematical community or in other cultures. The philosophy of mathematics is concerned with the role of language and logic in proofs, and mathematics as a language.

View More On Wikipedia.org
Recent contents Top users
  1. G

    Heat proof "waterless" valve for Unvented cylinder T&P connection to soil stack

    I have just had an unvented cylinder fitted, and the T&P valve is connected as per regs via a tundish, and then into the soil stack using a copper pipe. But I've had to ask the plumber to come back, because it looks like he hasn't done anything to prevent sewer gases from coming into the...
    • GeoffG
    • Thread
    • connection cylinder heat proof soil soil stack stack unvented unvented cylinder valve
    • Replies: 21
    • Forum: Australia
  2. R

    Dog proof waste pipe... yes dog proof :-)

    I do quite a bit of work at a large Veterinary Clinic near me. I've been asked to quote to do some more work. I need to fit a basin in the post op recover kennels. I have a cold supply, and they're going to confirm whether they need hot and if they do I'll use an instantaneous heater. The...
  3. T

    Installation of External Gas Combi Boiler in Tamper proof housing unit

    Good morning. In the process of buying a property with a gas combi boiler. It's currently installed in a wall mounted kitchen cabinet by the window. Would prefer to have the boiler installed on the outside wall of the kitchen to free up the cabinet space. Was advised by a builder that this may...
    • Tataboy
    • Thread
    • boiler combi combi boiler external gas housing installation oil proof
    • Replies: 36
    • Forum: Plumbing Jobs | The Job-board
  4. M

    Need advise, dealing with a potential thief in the company

    hi, Im in a bit of a tricky situation with a guy i employ, he has been accused of stealing 4 times, by 4 different people (not linked in any way) but never actually been able to prove it. a mobile phone, £20, (£60 from my own van!) and now a designer jacket. Now I'm not stupid, i know it has...
  5. R

    Damp proof membranes on concrete floor - urgent help please

    Hi there Can you please help - our builder seems to have little knowledge of buildings regulations so we are struggling with our extension/conversion. We are converting part of an internal garage plus existing room into a new kitchen. Problem is there are 2 different floor heights for the new...
  6. G

    Proof at last

    I now have evidence that Worcester installers truly believe that they (the individual) are the best thing since sliced bread! Chap I know loosely through previous employment and the merchants is a Worcester enthusiast. He's in my face book news feed and regularly promotes his business via that...
  7. P

    Will Standard Pipe Clips Make Pipes Stand Far Enough Of Wall To Fit Pump Valves?

    Just changed the plate hex on my Turbomax due to lots of rust flakes inside(despite corrosion inhibitor) causing poor hw performance. I need to flush the system and fit a filter. Because of system design, the only 22mm pipes that are accessible are on standard plastic pipe clips on a wall...
  8. P

    Rothenberger superfire 2 - safety/heat proof tips

    hi guys, Basically had to buy new blow lamp after 7 years! and I am trying to find the heat proof safety tips for it as I remember someone saying about them years a go and I was interested in trying one out. if anyone knows where I can get one please let me know Cheers Pooly
  9. B

    Fire proof paint

    A builder I know put in an oil tank next to the (residential) barn he just built. He painted the ship lap with normal black, then over painted it with this amazing fire proof paint. Its transparent and goes on like meths, very thin. 2 coats and it meets all BS regs for fire proofing. They even...
  10. B

    Child proof programmer for crazy old woman ?

    Ok I am after a programmer that Mother can turn on but not get at the controls ? Old people are not nice to look at and serve no useful purpose but kind of feel sorry for the old girl but losing her marbles ! She keeps messing up programmer well and anything she touches ! Sad thing old age as it...
  11. T

    Fool proof pricing?

    Hiya guys As a new business I'am doing okay with pricing at the moment(no major cock ups) but it takes me hours, obviously its important to give an accurate prices so that you get the job, But I'am finding that I never seem to be able to accurately give a price for materials I will use ie pipe...
  12. S

    damp proof membrane behind radiators?

    ive came across a problem as the house i had removed radiators from to let the customer redecorate, found rising damp in the walls. the company have stripped the plaster and put up a membrane to stop the damp coming through, they are in the middle of plastering over the membrane but they are...
  13. D

    One night only! This saturday night in the Plumbers Arms

    If you haven't already got membership then hurry to take advantage of this special offer! You need to be able to prove you're in the trade and have a minimum of 100 posts. See you on t'other side!
  14. K

    Help with gas NVQ level 3 portfolio

    I'm nearing the end of my NVQ level 3 gas maintenance course and i need to complete my portfolio. This includes proof of servicing cookers and meters(photographic evidence). I need to accompany a gas safe engineer on four jobs and tightness test, fault find and do gas rates etc. I do not want...
  15. R

    sound proof fire

    just had a call from a soundproofing company who need to put 3-4'' of soundproofing across the chimney breast. doing so will require the gas fire to be re-sited further out of the opening. has anyone else done this and can it be done without much problem?
  16. P

    Tamper Proof Central Heating Controls. Recommendations Please.

    I own a Victorian house split into 4 small flats. There has always been a problem with mould and since electricity costs have been increasing it's been getting worse. (The flats are all electric and the tenants are just not heating, or ventilating, them enough). I am now considering putting in a...
  17. W

    There are pages and pages of debate available online

    Attempting to finally resolve the flush pipe leaking at the pan problem. Use silicone! Don't use silicone! Bodge! Use the black rubber ones! Use the clear ribbed ones! Insert pipe half way into bung, insert bung half way into pan, face Mecca and push both pipe and cone into pan! Why is that...
  18. W

    Proof that recommendations aren't necessarily to be trusted.

    People keep recommending me. "You did some work for so and so and they said you were excellent.." "Christ, did they? I mean...well that's good to hear, how can I help?"
  19. M

    Best pipe tube carriers - how thief proof are they?

    Hi, I've got by fitting a few 3m lengths of pipe in the back of the van upto now as have to park on the road abd thought it was safer and cheaper:). But they always seem to be in the way! I've looked at the pipe tube carriers and wondered how safe they are ie they are an advert to thieves and...
  20. C

    tamper proof thermostat

    Hi can anyone help as i have a client who wants tamper proof thermostat fitting in several properties. These are to replace existing stats (conventional and combi system). they dont want the so call tamper proof ones wich can be unscrewed then altered by the tenants.any help would be much...
    • centurygrove
    • Thread
    • combi diy fitting funny gas heating jobs problem proof system thermostat
    • Replies: 8
    • Forum: Plumbing Jobs | The Job-board
Creating content since 2001. Untold Media.

Newest Plumbing Threads

Back
Top
AdBlock Detected

We get it, advertisements are annoying!

Sure, ad-blocking software does a great job at blocking ads, but it also blocks useful features of our website. For the best site experience please disable your AdBlocker.

I've Disabled AdBlock