inorganic chemistry - Reaction between alumina and aqueous sodium hydroxide, which one's right?

My chemistry textbook has a rather annoying irregularity.

It cites two different reactions for the same set of reactants (aluminium oxide, sodium hydroxide and water) without the slightest mention of a particular temperature or concentration. Here they are:

1. 
   
   

   In a chapter on the p-block elements:

   
   

   
   

   $$\ce{Al2O3 (s) + 6 NaOH (aq) + 3 H2O (l) -> 2 Na3[Al(OH)6] (aq)}$$

   
   

   
   


2. 
   

   In a chapter on metallurgy, under the topic of 'Extraction of aluminium from bauxite':

   
   

   
   

   $$\ce{Al2O3 (s) + 2 NaOH (aq) + 3 H2O (l) -> 2 Na[Al(OH)4] (aq)}$$

   
   

   
   
   

Which one of these is correct? Or are they both correct, depending on the situation? If so, under what conditions are they correct?