let A be closed-interval Subset of REAL ; :: thesis: for f being PartFunc of REAL ,REAL
for Z being open Subset of REAL st A c= Z & f = ((id Z) (#) ((sin * ln ) ^2 )) ^ & Z c= dom (cot * ln ) & Z = dom f & f | A is continuous holds
integral f,A = ((- (cot * ln )) . (upper_bound A)) - ((- (cot * ln )) . (lower_bound A))

let f be PartFunc of REAL ,REAL ; :: thesis: for Z being open Subset of REAL st A c= Z & f = ((id Z) (#) ((sin * ln ) ^2 )) ^ & Z c= dom (cot * ln ) & Z = dom f & f | A is continuous holds
integral f,A = ((- (cot * ln )) . (upper_bound A)) - ((- (cot * ln )) . (lower_bound A))

let Z be open Subset of REAL ; :: thesis: ( A c= Z & f = ((id Z) (#) ((sin * ln ) ^2 )) ^ & Z c= dom (cot * ln ) & Z = dom f & f | A is continuous implies integral f,A = ((- (cot * ln )) . (upper_bound A)) - ((- (cot * ln )) . (lower_bound A)) )
assume A1: ( A c= Z & f = ((id Z) (#) ((sin * ln ) ^2 )) ^ & Z c= dom (cot * ln ) & Z = dom f & f | A is continuous ) ; :: thesis: integral f,A = ((- (cot * ln )) . (upper_bound A)) - ((- (cot * ln )) . (lower_bound A))
then A2: ( f is_integrable_on A & f | A is bounded ) by INTEGRA5:10, INTEGRA5:11;
A3: - (cot * ln ) is_differentiable_on Z by A1, Th4;
Z c= dom ((id Z) (#) ((sin * ln ) ^2 )) by RFUNCT_1:11, A1;
then Z c= (dom (id Z)) /\ (dom ((sin * ln ) ^2 )) by VALUED_1:def 4;
then Z c= dom ((sin * ln ) ^2 ) by XBOOLE_1:18;
then A6: Z c= dom (sin * ln ) by VALUED_1:11;
B: for x being Real st x in Z holds
f . x = 1 / (x * ((sin . (ln . x)) ^2 ))
proof
let x be Real; :: thesis: ( x in Z implies f . x = 1 / (x * ((sin . (ln . x)) ^2 )) )
assume C: x in Z ; :: thesis: f . x = 1 / (x * ((sin . (ln . x)) ^2 ))
then (((id Z) (#) ((sin * ln ) ^2 )) ^ ) . x = 1 / (((id Z) (#) ((sin * ln ) ^2 )) . x) by RFUNCT_1:def 8, A1
.= 1 / (((id Z) . x) * (((sin * ln ) ^2 ) . x)) by VALUED_1:5
.= 1 / (x * (((sin * ln ) ^2 ) . x)) by FUNCT_1:35, C
.= 1 / (x * (((sin * ln ) . x) ^2 )) by VALUED_1:11
.= 1 / (x * ((sin . (ln . x)) ^2 )) by A6, FUNCT_1:22, C ;
hence f . x = 1 / (x * ((sin . (ln . x)) ^2 )) by A1; :: thesis: verum
end;
A7: for x being Real st x in dom ((- (cot * ln )) `| Z) holds
((- (cot * ln )) `| Z) . x = f . x
proof
let x be Real; :: thesis: ( x in dom ((- (cot * ln )) `| Z) implies ((- (cot * ln )) `| Z) . x = f . x )
assume x in dom ((- (cot * ln )) `| Z) ; :: thesis: ((- (cot * ln )) `| Z) . x = f . x
then A8: x in Z by A3, FDIFF_1:def 8;
then ((- (cot * ln )) `| Z) . x = 1 / (x * ((sin . (ln . x)) ^2 )) by A1, Th4
.= f . x by B, A8 ;
hence ((- (cot * ln )) `| Z) . x = f . x ; :: thesis: verum
end;
dom ((- (cot * ln )) `| Z) = dom f by A1, A3, FDIFF_1:def 8;
then (- (cot * ln )) `| Z = f by A7, PARTFUN1:34;
hence integral f,A = ((- (cot * ln )) . (upper_bound A)) - ((- (cot * ln )) . (lower_bound A)) by A1, A2, Th4, INTEGRA5:13; :: thesis: verum