Math Is Fun Forum

MasterofDisguise

Member

Registered: 2008-01-05

Posts: 68

A Challenge

Tell me if you can help me do the Rubiks puzzle i cant figure out how

Last edited by MasterofDisguise (2008-01-15 06:45:58)

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(im an ALIEN ) im kool (WHAT You cant steal my fridge!)]

AshJones555

Member

Registered: 2006-05-15

Posts: 19

Re: A Challenge

i can, i learnt from an instructional video where all the 6 faces are named, so the one on top would be the up face for example, shown as U and so on for all 6.
Then it's just a matter of memerizing algorithms

John E. Franklin

Member

Registered: 2005-08-29

Posts: 3,588

Re: A Challenge

I solve the top third, then the bottom third, then the middle ring.
I noticed on youtube, someone does the top, then middle, then bottom.
If you want to know my way, I'll help.

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igloo myrtilles fourmis

John E. Franklin

Member

Registered: 2005-08-29

Posts: 3,588

Re: A Challenge

Here's a move I invented that swaps two botom right corners, but
the other 6 corners remain perfect:
I'll call it "retrograde snake pond" because it involves a
move my brothers and I were playing with at snake pond
as children.  This move involves turning the right side of the
cube back towards you, if you are viewing the cube from
your head, just above the cube held out in front of you.
Instead of turning different sides of the cube, this move is
easiestly performed by rotating the entire cube in both
hands just after or while you do each right side pull back.  Pulling back
the right side means to rotate the right side counter-clockwise
a quarter turn as viewed from the right looking left at the
cube.  Now there are 12 of these right-side-pull-backs in
the move, but after the 4th and 8th right-pull-back you don't
do the whole-cube turn, which is why I call it "retrograde".
The whole-cube turn is to take the whole cube and keep the
top level and remaining the top and turn the cube a quarter
turn just like the way the Earth spins, counter-clockwise as
viewed from the top. 
Legend:
  right-side-pull-back-quarter-turn = pull-back
  whole-cube-Earth-turn-quarter-turn = turn-cube
  don't turn the cube = stay-cube
Now here's the steps to swap the bottom 2 corners on the right bottom:
1.pull-back, turn-cube
2.pull-back, turn-cube
3.pull-back, turn-cube
4.pull-back, stay-cube
5.pull-back, turn-cube
6.pull-back, turn-cube
7.pull-back, turn-cube
8.pull-back, stay-cube
9.pull-back, turn-cube
10.pull-back, turn-cube
11.pull-back, turn-cube
12.pull-back, stay-cube
That's it you are done!!!
The bottom of the cube will
have 2 corners swapped, but
also note that the bottom rotated
out of place by a quarter turn.
You will see this by inspection, and
can turn it if you want to align it up.

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igloo myrtilles fourmis

John E. Franklin

Member

Registered: 2005-08-29

Posts: 3,588

Re: A Challenge

Now here's another move I invented.
It maintains or keeps all corners in the
same locations, but it "twists" 3 corners
on the bottom of the cube.  Twisting
corners is like if you dissassemble the
cube and actually twist the corners 1/3
of a turn or 120 degrees.  Each corner
piece has 3 colors on it, and is one
piece of plastic.
So here's the 3 bottom corners twist move
I made up:
1.pull-back, turn-cube
2.pull-back, turn-cube
3.pull-back, turn-cube
4.pull-back, turn-cube
5.pull-back, turn-cube
6.pull-back, turn-cube
7.pull-back, turn-cube
8.pull-back, turn-cube
9.pull-back, turn-cube
10.pull-back, turn-cube
11.pull-back, turn-cube
12.pull-back, (turn-cube or not because you are done).
Flip whole cube over to see what happened to it.

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igloo myrtilles fourmis

Hopecantid

Member

Registered: 2008-04-08

Posts: 13

Re: A Challenge

Here's the video that I watched when I was first learning how to solve it:

http://www.youtube.com/watch?v=HsQIoPyfQzM

This is a slower method, but it's a good way to start and just learn some basic algorithms.  I can now solve it a lot faster and use short-cuts.

John E. Franklin

Member

Registered: 2005-08-29

Posts: 3,588

Re: A Challenge

"Xski Manuver":
This one swaps 2 diagonal corners on bottom of cube (sort of),
or it swaps two parallel adjacent botom pairs of corners; 
they're the same thing, just turn the bottom of the cube a
quarter turn to change the above 2 statements.
1.pull-back right side, turn cube ccw
2.pull-back right side, turn cube ccw
3.pull-back right side, turn cube ccw
4.pull-back right side.
5. pull-back left side, turn cube cw
6. pull-back left side, turn cube cw
7. pull-back left side, turn cube cw
8. pull-back left side
That's it, and also this move can be only 6 moves instead
of 8 if you see that 4&5 just turn the whole cube as a unit, so
4 & 5 go away really, just reorient the cube.
But the motion of 1 thru 8 is easier to remember in the long run.
(also note if this Xski is completed twice in a row, it does some nice stuff too
that is useful for a symmetrical 4BottomCorner twisting pattern)

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igloo myrtilles fourmis