Math Is Fun Forum
  Discussion about math, puzzles, games and fun.   Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ • π ƒ -¹ ² ³ °

You are not logged in.

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

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,394

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

Online

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

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,394

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

Online

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

bob bundy
Moderator
Registered: 2010-06-20
Posts: 6,311

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

View Image: equil.gif

You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

Offline

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

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,394

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

Online

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

bob bundy
Moderator
Registered: 2010-06-20
Posts: 6,311

Re: Biggest triangle in a cube

In a word, No.

Do you?

Bob


You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

Offline

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

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,394

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

Online

Board footer

Powered by FluxBB