Rubik's Cube

V. Solve the Bottom Edges

The end is near. At this point, there are three possibilities:

• NO bottom edge is in place
• Only 1 bottom edge is in place
• All 4 bottom edges are in place

If NO bottom edge is in place, then use the sequence below:

Before

M- B- M+ B2 M- B- M+

After

You only need to do this sequence once.

Note: Ignore the diagrams. As long as you keep the original top face on the top side, this sequence will guarantee that at least ONE bottom-edge cube will land in place afterwards.

If only ONE bottom edge is in place, then rotate the entire puzzle until the fixed bottom edge piece appears in the front. The remaining 3 bottom edges need to be swapped either clockwise or counter-clockwise.

Exchange Clockwise:		Exchange Counter-Clockwise:
M- B+ M+ B2 M- B+ M+		M- B- M+ B2 M- B- M+

You only need to memorize one of the above. For example, if you choose to memorize the "counter-clockwise" sequence, then use it twice to swap the 3 edges clockwise. Once all 4 bottom edges are arranged in place, get ready for the last step: Inversion.

Inversion

There are 3 different inversion schemes:

1. Invert 2 adjacent edges
2. Invert 2 opposite edges
3. Invert all 4 edges

For each inversion scheme, you must rotate the entire puzzle so that the inverted edges are positioned exactly like the ones in the diagrams, before attempting the sequence of moves!

~~~ Case #1: Invert two adjacent edges ~~~
		M- B- M+ B- M- B2 M+ B2 M- B- M+ B- M- B2 M+ B2		Result: The bottom edges are solved. In fact, the entire puzzle is solved.
________________________________________
~~~ Case #2: Invert two opposite edges ~~~
		M- B- M+ B- M- B2 M+ B2 M- B- M+ B- M- B2 M+ B2		Result: Two adjacent edges are still inverted. Go back to Case #1, do the sequence, and the bottom edges are solved.
________________________________________
~~~ Case #3: Invert all four edges ~~~
		M- B- M+ B- M- B2 M+ B2 M- B- M+ B- M- B2 M+ B2		Result: Two adjacent edges are still inverted. Go back to Case #1, do the sequence, and the bottom edges are solved.

As it turns out, the same sequence was used throughout all three cases. Now that your cube is solved, put it back in the box and return it to the toy store (you still have the reciept, don't you?); take the cash and buy a 6-pack!

THE END

@ Notation @ Top Edges @ Top Corners
@ Middle Edges @ Bottom Corners @ Bottom Edges

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