3   
    -12*x    
-------------
   __________
  /        8 
\/  1 - 9*x  
             
            
              $$- \frac{12 x^{3}}{\sqrt{- 9 x^{8} + 1}}$$
            
            
       
      
        
            
                     /         8  \
     2 |     12*x   |
-36*x *|1 + --------|
       |           8|
       \    1 - 9*x /
---------------------
       __________    
      /        8     
    \/  1 - 9*x      
             
            
              $$- \frac{36 x^{2} \cdot \left(\frac{12 x^{8}}{- 9 x^{8} + 1} + 1\right)}{\sqrt{- 9 x^{8} + 1}}$$
            
            
       
      
        
            
                    /         8            16  \
      |     78*x        648*x    |
-72*x*|1 + -------- + -----------|
      |           8             2|
      |    1 - 9*x    /       8\ |
      \               \1 - 9*x / /
----------------------------------
             __________           
            /        8            
          \/  1 - 9*x             
             
            
              $$- \frac{72 x \left(\frac{648 x^{16}}{\left(- 9 x^{8} + 1\right)^{2}} + \frac{78 x^{8}}{- 9 x^{8} + 1} + 1\right)}{\sqrt{- 9 x^{8} + 1}}$$