Question sur la dérivabilité

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Enregistré le : mer. oct. 17, 2018 4:32 pm

Question sur la dérivabilité

Message par adammuelta » mer. oct. 17, 2018 5:20 pm

Chops and Spins of table tennis can leave your head spinning

Coach was feeling somewhat lively. The look in his eye wasn't the one I have noticed in my kitty, since it ignites some helpless bug.

Richard McAfee held aloft the turtle egg using a chunk, and before placing it in play merrily stated,"Now, do not hit it that way (off to my best )."

I struck it dead , the ball flying off at a 90-degree angle to its planned path.

"Do not strike this one that way (to the left)."

It flew left than the ACLU.

"Now, do not hit this one to the internet."

You know so don't ask where it moved.

If you want to find more information about ping pong table, please check out our blog:

After all is said and done and you is left helpless in the hands of a specialist, there's but one thing to do. You draw yourself up , throw your shoulders, increase your head and shout:"Ping-Pong, Ping-Pong, Ping-Pong!" It drives them nuts.


Today's subject from the endless series called"Sports I Stink At" is correctly called table tennis. There is a flourishing little pocket of its own followers at the Chastain Park fitness center, playing 15 tables at the title of the Atlanta Table Tennis Association. It is quite a gumbo of humankind in the marketplace, a rich mixture of ages and nationalities that speaks to the worldwide appeal of this match.

McAfee is the club president, a fulltime trainer (who knew?) As well as the former contest manager for table tennis to get Atlanta's Olympics. He actually looks a nice and type ambassador, given to just the table tennis tease.

The uninitiated can input the gym on any given Tuesday or Sunday and also be struck dumb from the speed. So fast is the back-and-forth it appears to be a clock store on a double-espresso jag. There's the exact same type of ferocious downsized volleying in the two-time Olympian in his corner from the rank-and-file playing at the center of this room. Surely impressive is that the youthful U.S. junior winner, said to be great enough to provide even Forrest Gump a match.

The club thankfully takes walk in commerce, but McAfee admits that lots of decent amateur players have stumbled to the fitness center, taken from the roomful of turning functions and 90 miles kill shots and walked straight back out the doorway speaking just to themselves. That really is as edgy as table tennis has. If he can catch them punctually, McAfee will encourage them to remain and understand and build in their own game.

"You can not learn playing in your home, no matter how great you think you are," he explained.

They really paste on the plastic sheeting in their paddles prior to each night of drama. Think about this as the equal of a pool screwing together his own cue as he picks up the scent of blood. Never play with table tennis against these glue people. Read more information about ping pong paddle, click here.

Actual table tennis players wear special shoes and purchase $150 paddles and will make the ball do circus tricks.


None of this, obviously, applies to me personally. The Ping-Pong table of my childhood is sawdust someplace, and also the one in the cellar is really a fertile cobweb farm. Ironically, my game was missing so long that it was declared legally dead. When McAfee handed me one of the handsome paddles, he did not warn me by its own exceptionally tuned character, it'd send balls off its face. This was just like handing a driver's female student the keys to a Ferrari.

Finally, I got to the point where I can return two or one of his easiest shots someplace on the desk. However, the moment the part of spin was released, the entire surrounding region became a hard-hat zone. Balls were leaping around so blatantly I was awaiting Glenn Burns to stop and select six from the atmosphere to the week's lottery.

It was about this stage that McAfee started telling me about the subtleties. About the table tennisplayers are highly trained athletes. About how they possess a fraction of a second on every shot to ascertain if from the rebound to strike the ballwhat portion of this ball to hit and how to hit in order to take care of the twist and the rate. Hey, look, I would like to make it through this without sacrificing a watch, OK?

Sooner or later, I needed to try out a true game. It is my job. As I scanned the area to an opponent, it became evident that my sole opportunity to compete is to present table tennis. They frown on this here. I picked the only girl in the room, a slight, bespectacled woman who wasn't hoping to strike the ball throughout the gym walls.

Eleanor Leonhardt would not state how old she was, just hinting I had been younger than her kids. She explained her style for a chiseler. She will chop, chop, chop, returning , awaiting the error in the opposite end of the desk.

There was no waiting this moment. What a bloody rout. In five minutes it was finished, 21-1 for all those keeping score at home. Happily, she functioned that one ball to the web, also it might have been a shutout. To choose the best ping pong table, let's read the reviews: Best Ping Pong Robot/Table Tennis Robot And How To Choose. In a time such as this, along with your pride stripped nude, there's nothing left but the pointless gesture. It's the last resort for people who can not do. All together now:

"Ping-Pong, Ping-Pong, Ping-Pong!"
Modifié en dernier par adammuelta le sam. nov. 03, 2018 5:22 pm, modifié 1 fois.

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Enregistré le : sam. mars 12, 2016 6:59 pm
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Re: Question sur la dérivabilité

Message par donnerwetter » mer. oct. 17, 2018 5:26 pm

Tu peux t'en convaincre en appliquant l'égalité des accroissement finis à (y(h)-y(0))/h puis en faisant tendre h vers 0

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Enregistré le : dim. sept. 04, 2005 7:27 pm
Localisation : Versailles

Re: Question sur la dérivabilité

Message par JeanN » mer. oct. 17, 2018 6:28 pm

adammuelta a écrit :
mer. oct. 17, 2018 5:20 pm

On a écrit en cours : y'
--> 0 quand t--> 0 => y est dérivable en 0

gné ?

Merci d'avance
Si c'est écrit ainsi sans présentation de y, des domaines de définition, de dérivabilité, sans hypothèses de continuité en 0 ou autre, je confirme le "gné".
Peux-tu nous réécrire l'ensemble de l'énoncé avec la présentation des objets et les hypothèses ?
Professeur de maths MPSI Lycée Sainte-Geneviève

Messages : 5117
Enregistré le : dim. sept. 04, 2005 7:27 pm
Localisation : Versailles

Re: Question sur la dérivabilité

Message par JeanN » mer. oct. 17, 2018 6:30 pm

donnerwetter a écrit :
mer. oct. 17, 2018 5:26 pm
Tu peux t'en convaincre en appliquant l'égalité des accroissement finis à (y(h)-y(0))/h puis en faisant tendre h vers 0
Je pense que le résultat a été donné sans démonstration de façon à l'appliquer à des recollements de solutions d'équa diffs. Ca m'étonnerait qu'une sup en soit déjà au cours sur la dérivabilité et je parie que l'auteur de la question ignore tout de l'égalité des accroissements finis.
Professeur de maths MPSI Lycée Sainte-Geneviève


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