let A be non degenerated commutative Ring; for I, J being Ideal of A st sqrt I, sqrt J are_co-prime holds
I,J are_co-prime
let I, J be Ideal of A; ( sqrt I, sqrt J are_co-prime implies I,J are_co-prime )
assume A1:
sqrt I, sqrt J are_co-prime
; I,J are_co-prime
sqrt (I + J) =
sqrt ((sqrt I) + (sqrt J))
by Th14
.=
[#] A
by A1, Th13
;
hence
I,J are_co-prime
by Th13; verum