Answer:
 30
Explanation:
The ring operator signifies a composition of functions. The composition is evaluated right-to-left. That means the composition ...
 

should be interpreted to mean ...
 

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To evaluate f(g(6)), we first evaluate g(6):
 g(6) = 6² -5 = 31
Then we evaluate the function f using that as its argument:
 f(31) = 31 -1 = 30
 f(g(x)) = 30