svetazuna √a^(1/2)  :  √a^(-1/3) = 
= √(a^(1/2) : a^(-1/3) ) = 
= √a^(1/2 - (-1/3) = 
= √a^(1/2+1/3) = 
= √a^(3/6+2/6) = 
= √a^(5/6)