Rubik's Cube

what is the minimum number of moves required to form the the cross as shown in the figure (black cross) ? one move means one 90° rotation according to me it is 4 but i want other's answer also ??

#Combinatorics #RubiksCube

Easy Math Editor

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`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
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Comments

i think that you mean minimum number of moves in any permutation required to form a cross shown above .. if one move is 90 i think it is going to be 5 or 6 . a good problem let's try to find out what should be no of moves . as we can see the other colours do not matter it is going to be less tedious .

Shriram Lokhande - 6 years, 11 months ago

I've managed to do it in 5 moves, if you count $m$ moves as one move.

Daniel Liu - 6 years, 11 months ago

it will take one move for each non uniform coloured square

Jyotirmay Pa - 6 years, 11 months ago

1 move for the cross. Most crosses are about 6 - 8 moves. One move is a 90 degree or 180 degree rotation, by definition. If you practice the time should be about 3 seconds to make the cross. I can solve the whole cube in 30 seconds, and my average amount of moves for the whole cube (in case you want to know) is about 50 - 60.

Caleb Clark - 6 years, 6 months ago

which method do u use ?

Rishabh Jain - 6 years, 6 months ago

If you start with cross, then technically it takes zero moves.

Felix Lu - 5 years, 4 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$