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## #1 2012-05-30 06:39:56

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,037

### Biggest triangle in a cube

Find the area of the largest triangle that can be inscribed into a cube of side a.

Similarly: Find the area of the largest equilateral triangle that can be inscribed in a cube of side a.

Last edited by anonimnystefy (2012-05-30 06:43:04)

Here lies the reader who will never open this book. He is forever dead.
Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

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## #2 2012-07-06 09:59:36

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,037

### Re: Biggest triangle in a cube

Nothing, ha?

Here lies the reader who will never open this book. He is forever dead.
Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

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## #3 2012-07-06 19:30:25

bob bundy
Registered: 2010-06-20
Posts: 8,322

### Re: Biggest triangle in a cube

hi Stefy,

I must have been busy on 30th May.

I offer the solution to part two in the diagram below.  The area is easily worked out using half ABsinC and Pythag.

I suspect it is also the answer to part one.

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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## #4 2012-07-07 01:39:03

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,037

### Re: Biggest triangle in a cube

Do you have a proof that is the solution?

Last edited by anonimnystefy (2012-07-07 09:25:07)

Here lies the reader who will never open this book. He is forever dead.
Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

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## #5 2012-07-07 08:27:18

bob bundy
Registered: 2010-06-20
Posts: 8,322

### Re: Biggest triangle in a cube

In a word, No.

Do you?

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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## #6 2012-07-07 09:24:56

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,037

### Re: Biggest triangle in a cube

Nope. I will try to think of something.

Here lies the reader who will never open this book. He is forever dead.
Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

Offline