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Solving a rubik's cube

  1. Mar 7, 2007 #1
    Just an interesting question but has anybody here ever solved a Rubik's cube before? I need some serious help with solving one and it is driving me nuts! Anyone have some good tips?

  2. jcsd
  3. Mar 7, 2007 #2
    Snap appart the cubes, then re-assemble them by snapping them back together.
  4. Mar 7, 2007 #3
    I just learned a few weeks ago. Stumbled upon the last transformation needed pretty much by accident, too, while trying to apply group theory to the thing.

    Tips are hard to give out online. I would try to find some move sequences that change some of the stones without affecting most of the others.
  5. Mar 7, 2007 #4
    I've been solving one and I've actually accomplished a bit--first two layers done. Now I have the last layer to solve (which will probably be the most difficult, since I don't want to mess the others up!).

    I saw a guide online and picked up a few tips. The key to solving the cube is not to get "colors" in the right place...you can have one single-colored face "solved" but the pieces can be in completely wrong places. So, you have to get the pieces in the right places. (Example: The edge piece with red and yellow on it must be on the edge between the red and yellow faces.)

    Then you solve in layers. Pick a side to solve--say you choose yellow. First, you will solve the edge pieces on the chosen face (the pieces with only two colors). When you are done with this, your chosen face will look like a cross of yellow, and above each side's center piece will be that face's color (except for the bottom of course). Then solve the corner pieces for your chosen face. After that you'll have the whole first layer solved. Then, solve the edge pieces for the middle layer (this will be a little harder). I don't know how to solve the bottom, but it seems the "moves" get more complex as you progress to each subsequent layer.

    I learned that while you are solving the first layer, it is not necessary to keep the other layers in order, so you could use the bottom layer to "transport" pieces from one place to another to get them in the correct places. The side pieces on the second layer are a little harder but you can figure out the required moves with a little thought. The third layer I haven't done yet. ;) Good luck!
    Last edited: Mar 7, 2007
  6. Mar 7, 2007 #5
    Thats really where i'm having trouble. I can get the top side done and the first layer but i can't seem to position the edge pieces in the middle.

    And just think, once i'm done with this i can do one of these:surprised ....
  7. Mar 7, 2007 #6
    I can't remember exactly, but I think the way I solved the middle layer was by doing things like L2, U2, R, U2, L2. I think this would work if you can position the piece on the right on the bottom face so that if you were do R the piece would be in the correct position on the front face (of course this would mess up the top face). So, you would do L2, U2, R, U2, L2 and it wouldn't mess up any face. I also think I was able to solve the middle edge pieces by doing opposites one after another...that is, looking down on the middle layer from above, I solved the bottom right edge piece then top left, then bottom left then top right. The last piece was harder to get in the right spot without messing the others up and to tell you the truth, I got it by accident :X!

    I hope this helps!
  8. Mar 7, 2007 #7
    Someone here has a guide to solving these in their signature... I forget who though. :(
  9. Mar 7, 2007 #8
    Actually before even reading your post i managed to figure out how to place the middle pieces just by playing with it. I just have the last layer to deal with. By the way the bottom face to the original cross doesn't have to be a cross, right??
  10. Mar 7, 2007 #9
    The way I taught myself (which I think is the easiest), is to solve the 8 corner pieces first. This will allow you to solve the 12 edges without messing up the corners. If try to solve the edges first, then solving the corners will wind up messing up the edges. I hope this helps.
  11. Mar 7, 2007 #10
    I can solve the rubix cube in ~45 seconds. If anyone wants help, send me a PM. I can try and give you some hints.

    My junior year of high school (last year) was very boring, so I decided to learn how to solve a rubix cube! I succeeded. :) Obviously, my faster times are from memorization, then applying the methods I learned from previous solves.

    By the way, my method is the layer method. Solve the bottom layer, then middle layer, then top layer.

    As someone already mentioned, it's pointless to go by sides. Instead of thinking of the cube having 6 sides, you really need to think of it as 26 blocks that need to be arranged in the correct order and orientation. Even if one side is the same color, the blocks might not be arranged correctly to allow the other sides to be solved.

    As for the 8 corners -> sides method that the person above me mentioned, I haven't thought about it like that. I'm gonna go mess around with that now. ;)
    Last edited: Mar 7, 2007
  12. Mar 7, 2007 #11


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    Many years ago I was shown the 2 moves needed to solve the Rubik's cube. One "move" rotated a single corner leaving the rest unchanged. The other, much simpler move, rotated a edge piece.

    However, the corner rotation "move" was quite involved requiring between 20 and 30 individual rotations. I have long ago forgotten the sequence.
  13. Mar 7, 2007 #12
    That was my average as well when I used to play with that. :smile:

    I do it a bit different:

    First I position the bottom layer middle blocks, then I position three middle layer middle blocks. I leave one open to use as a "passing path" for bottom layer corner blocks to use faster formulas for positioning the bottom layer corner blocks. Then I position the bottom layer corner blocks. Then, with a single formula, I make the top one color without caring for positioning, with solving the last middle layer at the same time, if possible. Then I reposition the top layer blocks, usually with one or two formulas.
    Also, I always start with the same colors, that is theoretically not the best approach, but that way I know where everything must go and I hardly have to look.
    Last edited: Mar 7, 2007
  14. Mar 7, 2007 #13
    They are really easy once you get the hang of it.

    I solve a cross of one of the colours first, making sure taht the edge pieces are the correct ones by checking against the middle square of the adjacent sides. Then fill in the corners of teh side with the cross accept for one so that you can move back and forth without wrecking the rest of your side when trying to complete the rest of the cube.

    THen you solve the edge pieces accept for one aswell... line up the unsolved edge and the unsolved corner to get to make a cross on the top... it is too hard to explain fully, but if someone else knows this methiod they should be able to recognise it from that...
  15. Mar 7, 2007 #14


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    A third on the ~45 sec average. My best was a bit above 30 and I haven't been practicing lately, so it's gotten closer to about 1 minute. I first solve a 2x2x2, then 2x2x3, then what's called 'fixing edges', followed by completion of the first two layers (i.e. 2x3x3). LL is solved by first appropriately placing the corners, then orienting the corners, then correcting the edges. The F2L are mostly intuition at this point, but the LL is always memorized algorithms for me, depending on the state of cube at that point. I probably have only around 6 algorithms memorized + reflections.
  16. Mar 8, 2007 #15


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    Take a randomized cube, snap out a single piece, rotate it and replace it. Now give it to one of these 45sec whizes and watch them go crazy! :rofl:
  17. Mar 8, 2007 #16
    Mathematicians!!! :rofl: :rofl:
  18. Mar 8, 2007 #17


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  19. Mar 8, 2007 #18
    Hah, I did that once just to mess around with it; later on when I tried to solve it and had forgotten that I changed a single cube, I was really confused! >.<
  20. Mar 8, 2007 #19


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    I haven't played with one in years so I don't remember any of the moves, but...

    Instead of solving the whole cube, learn how to swap a side piece with the opposite side piece and how to swap a side piece with an adjacent side piece.

    The corners can usually be set up just by playing with the cube. I think I learned at least one formula for swapping corner pieces (that was the easiest swap I learned), but you can struggle by without one.

    If you don't know how to swap two side pieces, the last layer is just frustration.
  21. Mar 8, 2007 #20


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    :grumpy: :tongue: :grumpy:

    I have a really good booklet that shows how to do it, and it still takes me over 45 minutes following that. My sense of spatial orientations absolutely sucks. :redface:
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