Jon Tries to Explain How to Solve the Rubik's Cube
There are many many websites and videos explaining how
to solve the Rubik's Cube. Each does it a different way
and uses different modes of communication. This is my
contribution which uses a combination of text, pictures,
mnemonic word phrases, and short videos.
Note that learning to solve the cube by watching videos is NOT cheating.
Only a persistent obsessive genius can solve it all by themselves.
Very few people can solve the cube at all - it is NOT easy!
When (not if) you learn to solve it, you will have joined an elite group!
This is a beginner's method which is about the easiest to remember and do.
The aim here is to be able to solve the cube consistently and confidently.
If you want to go a little bit faster I have collected
a few simple optimizations for this beginner method.
If you want to go really fast (which is a worthy goal but is
certainly not necessary!) you can consult the
many resources at the end. There are also
some very entertaining videos there!
If you have a mathematical inclination you can see how
Group Theory applies to the cube. See the last section.
Cube Basics
The Rubik's cube appears to be 27 small cubes (cubies) arranged in a 3x3x3 stack.
It's actually something quite different and very clever.
There are 3 kinds of cubies:
Center Cubies - 6 of them - colored white, yellow, red, orange, blue, and green.
Edge Cubies - 12 of them - with two colors.
Corner Cubies - 8 of them - with three colors.
6 + 12 + 8 = 26. The 27th cubie is hidden inside at the center of the cube. You'll never see it.
The clever magic of the cube is that it can be twisted in every direction.
With just a few twists the cube becomes quite jumbled and scrambled up.
Your challenge - your mission (should you choose to accept it) -
is to restore the cube to the original state where
each face of the cube has same color on its 9 small faces.
The Overall Plan
We'll solve the cube a layer at a time in 7 steps from scrambled to solved.
First, for fun, here is a fast-forwarded demonstration of the 7 steps.
Scrambled - The state your cube is probably in right now.
White Edges - Matching the adjacent center cubie.
White Corners - The first layer is done.
Middle Layer - The cube is 2/3 solved! But we still have quite a ways to go...
The challenge is to put the last layer in order without disturbing the first two layers!
Yellow Edges in Cross - Not necessarily matching the adjacent center cubie.
Yellow Edges Matching - Matching the adjacent center cubie.
Yellow Corners Placed - Corners in right place but perhaps twisted.
Yellow Corners Twisted = Solved! Yay!!
White Edges
The first step of getting the white edges in place is fairly easy and somewhat intuitive.
It does take some degree of 3-dimensional aptitude.
This step is done by a series of simple short moves.
They are best explained with a video:
White Corners
Getting the white corners in their proper place is easier than the white edges.
There are essentially just two simple moves.
This completes the first layer. You should practice getting the first layer
in place several times before moving on to the next step.
You can solve the white layer, then the blue, then the orange, etc.
Middle Layer
This step uses just one fairly long move - with 8 twists. You can remember it with
the phrase "Away-Down-Back-Up". There is a symmetry to it that makes it memorable. You could also use the mnemonic word phrase ADBU-ADBU (away down back up - twice).
Again, practice this middle layer step several times before moving
on to the much more difficult third layer steps.
Yellow Edges in Cross
The edges on the yellow face will now look like one of the following 4 images.
Ignore the corners - we're only interested in the edges.
A - 2 yellow edges across from each other.
B - 2 yellow edges in a corner shape.
C - No yellow edges.
D - 4 yellow edges.
Now it gets harder.
Our moves can't disturb the first two layers!
The following video introduces a notation
that is very helpful for specifying the moves and remembering them.
It explains the "FRUgal ruffle" move and how to use it.
FRONT RIGHT UP right up front = FRU ruf = FRUgal ruffle
With the image A above you apply the FRUgal ruffle move once.
With B you apply the FRugal ruffle move twice.
With C you apply the FRugal ruffle move three times (thrice).
If you already have D, you are done with this step.
Note - Before doing the FRUgal ruffle moves for cases A and B make sure you
reposition the cube so that the edges match image A or B above.
What is a FRUgal ruffle? A decorative edge to fabric that is less expensive?
It doesn't really matter. It is a simply a mnemonic word phrase
and it sounds fun.
Yellow Edges Matching
The next goal is to have the yellow edges matching all around.
You will be able to turn the top yellow layer so that you will have
two edges that match the adjacent center. If you have four this step is done.
If only two this step is to get the other two to match.
As before, you must have the cube positioned properly before
executing the move - with the two matching edges (marked
with an X below) like one of these images:
The move to get the other two to match is "Ruu ru Ru ru" - the word phrase to
remember this is pronounced "Roooo roo Roo roo".
It consists of 4 twists to the right face interspersed with
counterclockwise twists of the upper face. Another way to say it
is:
right forward up twice
right back up
right forward up
right back up
See the symmetry and repetition?
Yellow Corners Placed
At this point we examine the yellow corners to see if
they are in the right 'place' or not. The corner cubie may be twisted
so that the yellow face is not up but we can see whether it belongs in that corner.
You will have none, one, or four corners in the right place.
With four, this step is done and you can move on to the next step.
The move we use to rotate 3 corners is this:
L-up, U
R-up, u
L-dn, U
R-dn, u
See the symmetries?
The catchy mnemonic word phrase I came up with is 'Lupper Dupper'.
This doesn't match the move exactly but should remind you of it.
Yellow Corners Twisted
We are almost done! We need to twist the yellow corners into their
correct positions. You will have some corners that need
twisting counterclockwise 120° and others that need
twisting counterclockwise 240° (or equivalently, twisting clockwise 120°).
It turns out that the total number of needed counterclockwise twists
will sum to a multiple of 360°.
We only need to learn one move which is used many times in a clever way.
It is this:
r d R D
The word phrase is 'reader
RADAR'.
Doing this move twice will twist the upper right
corner 120° counterclockwise. It messes with other cubes as well
but these will be restored before we're done.
If this move is done six times the cube will come back to
its original condition as if you had done nothing at all.
120 x 3 = 360 = 0.
Summary of Mnemonic Word Phrases
ADBU-ADBU
middle layer
FRUgal ruffle
yellow cross place
Roooo roo Roo roo
yellow cross match
Lupper Dupper
yellow corners place
reader RADAR
yellow corners twist
A Few Simple Optimizations
You can now solve the cube. Congratulations! You are to be
commended for your careful attention, your patience, and your persistence.
This last video will show you a few simple ways to go
a little bit faster when certain situations arise.
You'll need to learn 4 more sequences.
3 of them are closely related to ones that you already know.
The new mnemonic word phrases are 'FUR urf', 'You Rupper Dupper', and 'RADAR reader'.
These are similar to but different from 'FRUgal Ruffle', 'Lupper Dupper', and 'reader RADAR'.
If you also master these moves you can consider yourself a Rubik's cube expert.
Not a wizard but, yes, an expert.
Rubik's Cube Wizards are truly advanced evolved superhuman beings.
See the next section.
BG OR WY
It may help to remember that Blue/Green are opposite colors as are Orange/Red
and White/Yellow. When getting the first four cubes in place know that Orange is to the left of Green and Red is to the left of Blue.
Mimicking versus Linguistic Cogitating
When learning the algorithms it is best to learn like children
do - by mimicking and repeated practice.
As adults we often want to "understand" what we are doing and
want to repeat the letters R, U, F, etc out loud as if they are
some kind of mathematical formula. This doesn't really help.
Better is to be a child,
relax the chatter of your mind, and just DO and copy what you see.
Train your hand muscles, keep practicing, develop habits.
Get the moves into your body not your mind.
Alternate and Advanced Solving Methods and Other Resources
Solving the corners first is a quicker way than the beginner method described above. It's not as mind-bendingly complex or difficult as other speed methods. It is still a significant challenge but not as much!
ruwix.com - EVERYTHING you would ever want to know about The Cube including:
Click here to search youtube.com for 'rubik' and 'solve'.
They all seem to have the word 'easy' in their title. Yeah, right.
There is much more - look for yourself - on youtube.com and on the web!
Group Theory
Group Theory is a branch of abstract mathematics that deals with symmetry.
It applies directly to the Rubik's Cube. It is not easy but if you have
the inclination and the time to study, it can be quite beautiful.
See this introduction to group theory.
A more advanced presentation on permutation puzzles of all kinds including the Rubik's Cube
by Professor W. D. Joyner:
And another from Tom Davis that teaches group theory with the cube. He also wrote a cube solver program which can be downloaded here: geometer.org/rubik
Finally, the original (1979-81) mathematical treatise on the cube by David Singmaster.
