hello all(adsbygoogle = window.adsbygoogle || []).push({});

well now i see that there are alot of ways of proving things, but there is one way in which I dont understand at first sight, and that is proof by contradiction, is there anyway general way of understanding it? I have worked on so many proofs but these are the only ones i most likely to have trouble with.

I now normally assume that if i cant do the question then it must be a proof by contradiction, but see i dont understand how would such a proof be structured and how is it really proving something, the last proof i came across that i cant do is this one and I believe that it must be another proof by contradiction? so here we go

let f:[a,b]->R be a continuous function. let M>0 and f(x)<M for all x an element of [a,b]. define g:[a,b]->R by

[tex]g(x)=\frac{1}{M-f(x)}[/tex]

then show that g is bounded

**Physics Forums - The Fusion of Science and Community**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Proof by Contradiction

Loading...

Similar Threads for Proof Contradiction | Date |
---|---|

B Proof of a limit rule | Dec 19, 2017 |

B Proof of quotient rule using Leibniz differentials | Jun 10, 2017 |

B Don't follow one small step in proof | Jun 10, 2017 |

Integration result ln || - confusing and apparent contradictions! | Jun 24, 2012 |

**Physics Forums - The Fusion of Science and Community**