now for b, c being Real st b |^ n = a & b > 0 & c |^ n = a & c > 0 holds
not b <> clet b,
c be
Real;
( b |^ n = a & b > 0 & c |^ n = a & c > 0 implies not b <> c )assume that A35:
b |^ n = a
and A36:
b > 0
and A37:
c |^ n = a
and A38:
c > 0
and A39:
b <> c
;
contradiction end;
hence
for b1, b2 being Real holds
( ( a > 0 & b1 |^ n = a & b1 > 0 & b2 |^ n = a & b2 > 0 implies b1 = b2 ) & ( a = 0 & b1 = 0 & b2 = 0 implies b1 = b2 ) )
; verum