let a, b, c, d, n be Nat; ( a,b,c are_mutually_coprime & (a * b) * c = d |^ n implies ex k being Nat st a = k |^ n )
assume A1:
a,b,c are_mutually_coprime
; ( not (a * b) * c = d |^ n or ex k being Nat st a = k |^ n )
assume
(a * b) * c = d |^ n
; ex k being Nat st a = k |^ n
then
ex k1 being Nat st k1 |^ n = a * b
by A1, NEWTON02:30, INT_2:26;
hence
ex k being Nat st a = k |^ n
by A1, NEWTON02:30; verum