let r be Real; :: thesis: ( r <> 0 implies ( (1 / r) (#) (exp_R * (AffineMap r,0 )) is_differentiable_on REAL & ( for x being Real holds (((1 / r) (#) (exp_R * (AffineMap r,0 ))) `| REAL ) . x = (exp_R * (AffineMap r,0 )) . x ) ) )
assume B:
r <> 0
; :: thesis: ( (1 / r) (#) (exp_R * (AffineMap r,0 )) is_differentiable_on REAL & ( for x being Real holds (((1 / r) (#) (exp_R * (AffineMap r,0 ))) `| REAL ) . x = (exp_R * (AffineMap r,0 )) . x ) )
A:
[#] REAL = dom ((1 / r) (#) (exp_R * (AffineMap r,0 )))
by FUNCT_2:def 1;
A1:
[#] REAL = dom (exp_R * (AffineMap r,0 ))
by FUNCT_2:def 1;
A2:
[#] REAL = dom (AffineMap r,0 )
by FUNCT_2:def 1;
A3:
for x being Real st x in REAL holds
(AffineMap r,0 ) . x = (r * x) + 0
by JORDAN16:def 3;
then A4:
( AffineMap r,0 is_differentiable_on REAL & ( for x being Real st x in [#] REAL holds
((AffineMap r,0 ) `| REAL ) . x = r ) )
by A2, FDIFF_1:31;
for x being Real st x in REAL holds
exp_R * (AffineMap r,0 ) is_differentiable_in x
then A5:
exp_R * (AffineMap r,0 ) is_differentiable_on REAL
by A1, FDIFF_1:16;
for x being Real st x in REAL holds
(((1 / r) (#) (exp_R * (AffineMap r,0 ))) `| REAL ) . x = (exp_R * (AffineMap r,0 )) . x
proof
let x be
Real;
:: thesis: ( x in REAL implies (((1 / r) (#) (exp_R * (AffineMap r,0 ))) `| REAL ) . x = (exp_R * (AffineMap r,0 )) . x )
assume
x in REAL
;
:: thesis: (((1 / r) (#) (exp_R * (AffineMap r,0 ))) `| REAL ) . x = (exp_R * (AffineMap r,0 )) . x
A6:
AffineMap r,
0 is_differentiable_in x
by A4, FDIFF_1:16;
(((1 / r) (#) (exp_R * (AffineMap r,0 ))) `| REAL ) . x =
(1 / r) * (diff (exp_R * (AffineMap r,0 )),x)
by A, A5, FDIFF_1:28
.=
(1 / r) * ((exp_R . ((AffineMap r,0 ) . x)) * (diff (AffineMap r,0 ),x))
by A6, TAYLOR_1:19
.=
(1 / r) * ((exp_R . ((AffineMap r,0 ) . x)) * (((AffineMap r,0 ) `| REAL ) . x))
by A4, FDIFF_1:def 8
.=
(1 / r) * ((exp_R . ((AffineMap r,0 ) . x)) * r)
by A2, A3, FDIFF_1:31
.=
(r * (1 / r)) * (exp_R . ((AffineMap r,0 ) . x))
.=
(r / r) * (exp_R . ((AffineMap r,0 ) . x))
by XCMPLX_1:100
.=
1
* (exp_R . ((AffineMap r,0 ) . x))
by B, XCMPLX_1:60
.=
(exp_R * (AffineMap r,0 )) . x
by A1, FUNCT_1:22
;
hence
(((1 / r) (#) (exp_R * (AffineMap r,0 ))) `| REAL ) . x = (exp_R * (AffineMap r,0 )) . x
;
:: thesis: verum
end;
hence
( (1 / r) (#) (exp_R * (AffineMap r,0 )) is_differentiable_on REAL & ( for x being Real holds (((1 / r) (#) (exp_R * (AffineMap r,0 ))) `| REAL ) . x = (exp_R * (AffineMap r,0 )) . x ) )
by A5, A, FDIFF_1:28; :: thesis: verum