There are several planes which are 1cm away from the three vertices of △ ABC whose sides are 3cm As the title 2. How many out of plane lines are there in the 12 diagonals of the cuboid? 3. Let f (x) = 1 + X / 1-x, and let F 1 (x) = f (x), f K + 1 (x) = f (f K (x)), k = 1,2.. then f 2007 (x) =?

There are several planes which are 1cm away from the three vertices of △ ABC whose sides are 3cm As the title 2. How many out of plane lines are there in the 12 diagonals of the cuboid? 3. Let f (x) = 1 + X / 1-x, and let F 1 (x) = f (x), f K + 1 (x) = f (f K (x)), k = 1,2.. then f 2007 (x) =?

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