let m1 be Nat; for i1 being Integer
for q being Rational st q = i1 / m1 & m1 <> 0 & i1,m1 are_coprime holds
( i1 = numerator q & m1 = denominator q )
let i1 be Integer; for q being Rational st q = i1 / m1 & m1 <> 0 & i1,m1 are_coprime holds
( i1 = numerator q & m1 = denominator q )
let q be Rational; ( q = i1 / m1 & m1 <> 0 & i1,m1 are_coprime implies ( i1 = numerator q & m1 = denominator q ) )
assume that
A1:
q = i1 / m1
and
A2:
m1 <> 0
and
A3:
i1,m1 are_coprime
; ( i1 = numerator q & m1 = denominator q )
A4:
i1 gcd m1 = 1
by A3, INT_2:def 3;
ex m being Nat st
( i1 = (numerator q) * m & m1 = (denominator q) * m )
by A1, A2, RAT_1:27;
then consider m being Nat such that
A5:
i1 = m * (numerator q)
and
A6:
m1 = m * (denominator q)
;
A7:
m divides i1
by A5;
A8:
m divides m1
by A6;
m divides 1
by A4, A7, A8, INT_2:def 2;
then
m = 1
by WSIERP_1:15;
hence
( i1 = numerator q & m1 = denominator q )
by A6, A5; verum