Math Is Fun Forum

yuyukin

Member

Registered: 2009-03-21

Posts: 13

Second problem not for nervous

   if   

smiyc86

Member

Registered: 2009-03-19

Posts: 78

Re: Second problem not for nervous

6

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I love Maths and Music ... dunno which more

yuyukin

Member

Registered: 2009-03-21

Posts: 13

Re: Second problem not for nervous

Answer is incorrect!

mathsyperson

Moderator

Registered: 2005-06-22

Posts: 4,900

Re: Second problem not for nervous

It depends what you mean by y'.
If it's dy/dx, then y' = 2x, and so putting x=3 into that gives an answer of 6.

That's the only useful meaning I can think of.

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Why did the vector cross the road?
It wanted to be normal.

Ricky

Moderator

Registered: 2005-12-04

Posts: 3,791

Re: Second problem not for nervous

It might be worth it to point out that yuyukin has the same IP address as unnihilator.

Yuyukin, if you indeed are the same person (and I don't know if that's true), then please avoid using multiple accounts in the future.  It makes things look suspicious, though you've done nothing wrong as of yet.

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"In the real world, this would be a problem.  But in mathematics, we can just define a place where this problem doesn't exist.  So we'll go ahead and do that now..."

yuyukin

Member

Registered: 2009-03-21

Posts: 13

Re: Second problem not for nervous

http://eqworld.ipmnet.ru/forum/viewtopic.php?f=3&t=143

Ricky

Moderator

Registered: 2005-12-04

Posts: 3,791

Re: Second problem not for nervous

Based on that page, your calculus is wrong.

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"In the real world, this would be a problem.  But in mathematics, we can just define a place where this problem doesn't exist.  So we'll go ahead and do that now..."

JaneFairfax

Member

Registered: 2007-02-23

Posts: 6,868

Re: Second problem not for nervous

yuyukin, you seem to think that that the derivative of

is

I can only describe what you posted on EqWorld in one Russian word: ВЗДОР!

yuyukin

Member

Registered: 2009-03-21

Posts: 13

Re: Second problem not for nervous

Based on that page, your calculus is wrong.

Show, in what a mistake?: for example, "1=3" - a mistake, because "1=1", "3=3"!

yuyukin

Member

Registered: 2009-03-21

Posts: 13

Re: Second problem not for nervous

...

is

I can only describe what you posted on EqWorld in one Russian word: ВЗДОР!

When Kopernik has told, what not the Sun rotates around of the Earth, and on the contrary, to it have told:

ВЗДОР!

And you show in detail as I have shown in
http://eqworld.ipmnet.ru/forum/viewtopic.php?f=3&t=143

, as you consider CORRECTLY, prove!

In the mathematician to tell INCORRECTLY a little, it is necessary to show AS CORRECTLY!

I showed AS CORRECTLY!

smiyc86

Member

Registered: 2009-03-19

Posts: 78

Re: Second problem not for nervous

http://eqworld.ipmnet.ru/forum/viewtopic.php?f=3&t=143

u need some revisions on the definitions of derivatives dude ...

the step 2 which u have derived from step 1 in eqworld .... is math .... please understand the definition of derivative ...

for example ...
u have taken square and its perimeter as a base to derive .... (y)' = 2√y 

i can derive from a cube and its surface area to derive ... (y)' = 3* y^2/3 ..... now which one will u follow ???

here is the proof similar to urs

if 'a' ia side of a cube ....

then a³ is its volume

now (a³)' = 3a² , which is half the total surface area ... and proceeding in ur manner .. substituting y=a^3 ... we get (y)' = 3* y^2/3

NOTE : if u substitute y = p² ... as u have done

then (y)' = 2pp'

= 2√y * (√y)' = 2√y / 2√y = 1 ..... this is the mathematical proof

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I love Maths and Music ... dunno which more

JaneFairfax

Member

Registered: 2007-02-23

Posts: 6,868

Re: Second problem not for nervous

[align=center]

[/align]

Ответ

, не

!

Last edited by JaneFairfax (2009-03-30 10:57:16)

John E. Franklin

Member

Registered: 2005-08-29

Posts: 3,588

Re: Second problem not for nervous

"ВЗДОР" means "nonsense".
That middle letter "Д" sure is strange!

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igloo myrtilles fourmis

Devantè

Real Member

Registered: 2006-07-14

Posts: 6,400

Re: Second problem not for nervous

Lawl. Reminds me of Anthony R Brown.

Why does it look like he's trying to apply an incorrect form of the chain rule in an unapplicable question? O_o

Only answer I get is 6.

yuyukin

Member

Registered: 2009-03-21

Posts: 13

Re: Second problem not for nervous

To JaneFairfax:
You are wrong! This greatest error!
It turns out, what

, if

and

,

???

[align=center]

[/align]

Ответ

, не

!

Why???!!!

JaneFairfax

Member

Registered: 2007-02-23

Posts: 6,868

Re: Second problem not for nervous

[align=center]

[/align]

Ответ

, не

!

Why???!!!

Why not???!!!

yuyukin

Member

Registered: 2009-03-21

Posts: 13

Re: Second problem not for nervous

Derivative of volume of a cube - the area of its halfsurface.

JaneFairfax

Member

Registered: 2007-02-23

Posts: 6,868

Re: Second problem not for nervous

That’s true, but what’s that got to do with the previous problem?

Devantè

Real Member

Registered: 2006-07-14

Posts: 6,400

Re: Second problem not for nervous

The antiderivative of 2πr is the area of a circle, too.

Hooray for randomness? <_<