Numere

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alex2008
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Numere

Post by alex2008 »

Aratati ca nu exista numere naturale a,b,c care verifice simultan egalitatile : \( b+c=a+1 \) si \( b^2+c^2=a^2 \) .
. A snake that slithers on the ground can only dream of flying through the air.
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miruna.lazar
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Post by miruna.lazar »

\( b^2 +c^2 = a ^2 \) sunt numere pitagorice. am mai facut o data acest tip de exercitiu : uite-te aici ( http://www.mateforum.ro/viewtopic.php?t=2473 )
Last edited by miruna.lazar on Sat Nov 29, 2008 4:09 pm, edited 1 time in total.
alex2008
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Post by alex2008 »

Da , sunt numere pitagorice . Acest exercitiu e usor de inteles prin paritate . :)
. A snake that slithers on the ground can only dream of flying through the air.
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naruto
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Post by naruto »

Aaaa... Luam toate cazurie:

1). b, c pare => b+c si \( b^2+c^2 \) sunt pare => a+1 si a^2 sunt pare => imposibil, fiindca a nu poate fi si par, si impar in acelasi timp.

2). b, c - impare => b+c si \( b^2+c^2 \) sunt pare ... la fel ca mai sus.

3). b par, c impar => b+c si \( b^2+c^2 \) sunt impare => a+1 si a^2 sunt impare => imposibil

4). b impar, c par => la fel ca 3).

Naruto, don't ever forget: gandeste-te si la paritate!!!
Asta a fost principiul paritatii personalizat :lol: :lol: :lol:
The important thing is not to stop questioning. Albert Einstein.
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