let a be Real; for Z being open Subset of REAL
for f1, f2 being PartFunc of REAL,REAL st Z c= dom ((1 / (log (number_e,a))) (#) ((exp_R * f1) (#) f2)) & ( for x being Real st x in Z holds
( f1 . x = x * (log (number_e,a)) & f2 . x = x - (1 / (log (number_e,a))) ) ) & a > 0 & a <> 1 holds
( (1 / (log (number_e,a))) (#) ((exp_R * f1) (#) f2) is_differentiable_on Z & ( for x being Real st x in Z holds
(((1 / (log (number_e,a))) (#) ((exp_R * f1) (#) f2)) `| Z) . x = x * (a #R x) ) )
let Z be open Subset of REAL; for f1, f2 being PartFunc of REAL,REAL st Z c= dom ((1 / (log (number_e,a))) (#) ((exp_R * f1) (#) f2)) & ( for x being Real st x in Z holds
( f1 . x = x * (log (number_e,a)) & f2 . x = x - (1 / (log (number_e,a))) ) ) & a > 0 & a <> 1 holds
( (1 / (log (number_e,a))) (#) ((exp_R * f1) (#) f2) is_differentiable_on Z & ( for x being Real st x in Z holds
(((1 / (log (number_e,a))) (#) ((exp_R * f1) (#) f2)) `| Z) . x = x * (a #R x) ) )
let f1, f2 be PartFunc of REAL,REAL; ( Z c= dom ((1 / (log (number_e,a))) (#) ((exp_R * f1) (#) f2)) & ( for x being Real st x in Z holds
( f1 . x = x * (log (number_e,a)) & f2 . x = x - (1 / (log (number_e,a))) ) ) & a > 0 & a <> 1 implies ( (1 / (log (number_e,a))) (#) ((exp_R * f1) (#) f2) is_differentiable_on Z & ( for x being Real st x in Z holds
(((1 / (log (number_e,a))) (#) ((exp_R * f1) (#) f2)) `| Z) . x = x * (a #R x) ) ) )
assume that
A1:
Z c= dom ((1 / (log (number_e,a))) (#) ((exp_R * f1) (#) f2))
and
A2:
for x being Real st x in Z holds
( f1 . x = x * (log (number_e,a)) & f2 . x = x - (1 / (log (number_e,a))) )
and
A3:
a > 0
and
A4:
a <> 1
; ( (1 / (log (number_e,a))) (#) ((exp_R * f1) (#) f2) is_differentiable_on Z & ( for x being Real st x in Z holds
(((1 / (log (number_e,a))) (#) ((exp_R * f1) (#) f2)) `| Z) . x = x * (a #R x) ) )
A5:
Z c= dom ((exp_R * f1) (#) f2)
by A1, VALUED_1:def 5;
then A6:
Z c= (dom (exp_R * f1)) /\ (dom f2)
by VALUED_1:def 4;
then A7:
Z c= dom (exp_R * f1)
by XBOOLE_1:18;
A8:
for x being Real st x in Z holds
f2 . x = (1 * x) + (- (1 / (log (number_e,a))))
A10:
for x being Real st x in Z holds
f1 . x = x * (log (number_e,a))
by A2;
then A11:
exp_R * f1 is_differentiable_on Z
by A3, A7, Th11;
A12:
Z c= dom f2
by A6, XBOOLE_1:18;
then A13:
f2 is_differentiable_on Z
by A8, FDIFF_1:23;
then A14:
(exp_R * f1) (#) f2 is_differentiable_on Z
by A5, A11, FDIFF_1:21;
A15:
log (number_e,a) <> 0
proof
A16:
number_e <> 1
by TAYLOR_1:11;
assume
log (
number_e,
a)
= 0
;
contradiction
then
log (
number_e,
a)
= log (
number_e,1)
by SIN_COS2:13, TAYLOR_1:13;
then a =
number_e to_power (log (number_e,1))
by A3, A16, POWER:def 3, TAYLOR_1:11
.=
1
by A16, POWER:def 3, TAYLOR_1:11
;
hence
contradiction
by A4;
verum
end;
for x being Real st x in Z holds
(((1 / (log (number_e,a))) (#) ((exp_R * f1) (#) f2)) `| Z) . x = x * (a #R x)
proof
let x be
Real;
( x in Z implies (((1 / (log (number_e,a))) (#) ((exp_R * f1) (#) f2)) `| Z) . x = x * (a #R x) )
assume A17:
x in Z
;
(((1 / (log (number_e,a))) (#) ((exp_R * f1) (#) f2)) `| Z) . x = x * (a #R x)
then A18:
(exp_R * f1) . x =
exp_R . (f1 . x)
by A7, FUNCT_1:12
.=
exp_R . (x * (log (number_e,a)))
by A2, A17
.=
a #R x
by A3, Th1
;
(((1 / (log (number_e,a))) (#) ((exp_R * f1) (#) f2)) `| Z) . x =
(1 / (log (number_e,a))) * (diff (((exp_R * f1) (#) f2),x))
by A1, A14, A17, FDIFF_1:20
.=
(1 / (log (number_e,a))) * ((((exp_R * f1) (#) f2) `| Z) . x)
by A14, A17, FDIFF_1:def 7
.=
(1 / (log (number_e,a))) * (((f2 . x) * (diff ((exp_R * f1),x))) + (((exp_R * f1) . x) * (diff (f2,x))))
by A5, A11, A13, A17, FDIFF_1:21
.=
(1 / (log (number_e,a))) * (((f2 . x) * (((exp_R * f1) `| Z) . x)) + (((exp_R * f1) . x) * (diff (f2,x))))
by A11, A17, FDIFF_1:def 7
.=
(1 / (log (number_e,a))) * (((f2 . x) * (((exp_R * f1) `| Z) . x)) + (((exp_R * f1) . x) * ((f2 `| Z) . x)))
by A13, A17, FDIFF_1:def 7
.=
(1 / (log (number_e,a))) * (((f2 . x) * ((a #R x) * (log (number_e,a)))) + (((exp_R * f1) . x) * ((f2 `| Z) . x)))
by A3, A10, A7, A17, Th11
.=
(1 / (log (number_e,a))) * (((f2 . x) * ((a #R x) * (log (number_e,a)))) + (((exp_R * f1) . x) * 1))
by A12, A8, A17, FDIFF_1:23
.=
(1 / (log (number_e,a))) * ((((f2 . x) * (log (number_e,a))) + 1) * (a #R x))
by A18
.=
(1 / (log (number_e,a))) * ((((x - (1 / (log (number_e,a)))) * (log (number_e,a))) + 1) * (a #R x))
by A2, A17
.=
((1 / (log (number_e,a))) * (((x * (log (number_e,a))) - ((1 / (log (number_e,a))) * (log (number_e,a)))) + 1)) * (a #R x)
.=
((1 / (log (number_e,a))) * (((x * (log (number_e,a))) - 1) + 1)) * (a #R x)
by A15, XCMPLX_1:106
.=
(((1 / (log (number_e,a))) * (log (number_e,a))) * x) * (a #R x)
.=
(1 * x) * (a #R x)
by A15, XCMPLX_1:106
.=
x * (a #R x)
;
hence
(((1 / (log (number_e,a))) (#) ((exp_R * f1) (#) f2)) `| Z) . x = x * (a #R x)
;
verum
end;
hence
( (1 / (log (number_e,a))) (#) ((exp_R * f1) (#) f2) is_differentiable_on Z & ( for x being Real st x in Z holds
(((1 / (log (number_e,a))) (#) ((exp_R * f1) (#) f2)) `| Z) . x = x * (a #R x) ) )
by A1, A14, FDIFF_1:20; verum