let r, x be Real; for m being Element of NAT st 0 < r holds
( (Partial_Sums (Maclaurin sin ,].(- r),r.[,x)) . ((2 * m) + 1) = (Partial_Sums (x P_sin )) . m & (Partial_Sums (Maclaurin cos ,].(- r),r.[,x)) . ((2 * m) + 1) = (Partial_Sums (x P_cos )) . m )
let m be Element of NAT ; ( 0 < r implies ( (Partial_Sums (Maclaurin sin ,].(- r),r.[,x)) . ((2 * m) + 1) = (Partial_Sums (x P_sin )) . m & (Partial_Sums (Maclaurin cos ,].(- r),r.[,x)) . ((2 * m) + 1) = (Partial_Sums (x P_cos )) . m ) )
assume A1:
r > 0
; ( (Partial_Sums (Maclaurin sin ,].(- r),r.[,x)) . ((2 * m) + 1) = (Partial_Sums (x P_sin )) . m & (Partial_Sums (Maclaurin cos ,].(- r),r.[,x)) . ((2 * m) + 1) = (Partial_Sums (x P_cos )) . m )
thus
(Partial_Sums (Maclaurin sin ,].(- r),r.[,x)) . ((2 * m) + 1) = (Partial_Sums (x P_sin )) . m
(Partial_Sums (Maclaurin cos ,].(- r),r.[,x)) . ((2 * m) + 1) = (Partial_Sums (x P_cos )) . mproof
defpred S1[
Element of
NAT ]
means (Partial_Sums (Maclaurin sin ,].(- r),r.[,x)) . ((2 * $1) + 1) = (Partial_Sums (x P_sin )) . $1;
A2:
for
k being
Element of
NAT st
S1[
k] holds
S1[
k + 1]
proof
let k be
Element of
NAT ;
( S1[k] implies S1[k + 1] )
assume A3:
S1[
k]
;
S1[k + 1]
(Partial_Sums (Maclaurin sin ,].(- r),r.[,x)) . ((2 * (k + 1)) + 1) =
((Partial_Sums (Maclaurin sin ,].(- r),r.[,x)) . ((2 * k) + 2)) + ((Maclaurin sin ,].(- r),r.[,x) . ((2 * k) + 3))
by SERIES_1:def 1
.=
((Partial_Sums (Maclaurin sin ,].(- r),r.[,x)) . ((2 * k) + 2)) + ((((- 1) |^ (k + 1)) * (x |^ ((2 * (k + 1)) + 1))) / (((2 * (k + 1)) + 1) ! ))
by A1, Th20
.=
((Partial_Sums (Maclaurin sin ,].(- r),r.[,x)) . (((2 * k) + 1) + 1)) + ((x P_sin ) . (k + 1))
by SIN_COS:def 24
.=
(((Partial_Sums (Maclaurin sin ,].(- r),r.[,x)) . ((2 * k) + 1)) + ((Maclaurin sin ,].(- r),r.[,x) . (2 * (k + 1)))) + ((x P_sin ) . (k + 1))
by SERIES_1:def 1
.=
(((Partial_Sums (Maclaurin sin ,].(- r),r.[,x)) . ((2 * k) + 1)) + 0 ) + ((x P_sin ) . (k + 1))
by A1, Th20
.=
(Partial_Sums (x P_sin )) . (k + 1)
by A3, SERIES_1:def 1
;
hence
S1[
k + 1]
;
verum
end;
(Partial_Sums (Maclaurin sin ,].(- r),r.[,x)) . ((2 * 0 ) + 1) =
((Partial_Sums (Maclaurin sin ,].(- r),r.[,x)) . (2 * 0 )) + ((Maclaurin sin ,].(- r),r.[,x) . ((2 * 0 ) + 1))
by SERIES_1:def 1
.=
((Maclaurin sin ,].(- r),r.[,x) . (2 * 0 )) + ((Maclaurin sin ,].(- r),r.[,x) . ((2 * 0 ) + 1))
by SERIES_1:def 1
.=
0 + ((Maclaurin sin ,].(- r),r.[,x) . ((2 * 0 ) + 1))
by A1, Th20
.=
(((- 1) |^ 0 ) * (x |^ ((2 * 0 ) + 1))) / (((2 * 0 ) + 1) ! )
by A1, Th20
.=
(x P_sin ) . 0
by SIN_COS:def 24
.=
(Partial_Sums (x P_sin )) . 0
by SERIES_1:def 1
;
then A4:
S1[
0 ]
;
for
n being
Element of
NAT holds
S1[
n]
from NAT_1:sch 1(A4, A2);
hence
(Partial_Sums (Maclaurin sin ,].(- r),r.[,x)) . ((2 * m) + 1) = (Partial_Sums (x P_sin )) . m
;
verum
end;
defpred S1[ Element of NAT ] means (Partial_Sums (Maclaurin cos ,].(- r),r.[,x)) . ((2 * $1) + 1) = (Partial_Sums (x P_cos )) . $1;
A5:
for k being Element of NAT st S1[k] holds
S1[k + 1]
proof
let k be
Element of
NAT ;
( S1[k] implies S1[k + 1] )
assume A6:
S1[
k]
;
S1[k + 1]
(Partial_Sums (Maclaurin cos ,].(- r),r.[,x)) . ((2 * (k + 1)) + 1) =
((Partial_Sums (Maclaurin cos ,].(- r),r.[,x)) . ((2 * k) + 2)) + ((Maclaurin cos ,].(- r),r.[,x) . ((2 * (k + 1)) + 1))
by SERIES_1:def 1
.=
((Partial_Sums (Maclaurin cos ,].(- r),r.[,x)) . ((2 * k) + 2)) + 0
by A1, Th20
.=
(Partial_Sums (Maclaurin cos ,].(- r),r.[,x)) . (((2 * k) + 1) + 1)
.=
((Partial_Sums (Maclaurin cos ,].(- r),r.[,x)) . ((2 * k) + 1)) + ((Maclaurin cos ,].(- r),r.[,x) . ((2 * k) + 2))
by SERIES_1:def 1
.=
((Partial_Sums (x P_cos )) . k) + ((((- 1) |^ (k + 1)) * (x |^ (2 * (k + 1)))) / ((2 * (k + 1)) ! ))
by A1, A6, Th20
.=
((Partial_Sums (x P_cos )) . k) + ((x P_cos ) . (k + 1))
by SIN_COS:def 25
.=
(Partial_Sums (x P_cos )) . (k + 1)
by SERIES_1:def 1
;
hence
S1[
k + 1]
;
verum
end;
(Partial_Sums (Maclaurin cos ,].(- r),r.[,x)) . ((2 * 0 ) + 1) =
((Partial_Sums (Maclaurin cos ,].(- r),r.[,x)) . (2 * 0 )) + ((Maclaurin cos ,].(- r),r.[,x) . ((2 * 0 ) + 1))
by SERIES_1:def 1
.=
((Maclaurin cos ,].(- r),r.[,x) . (2 * 0 )) + ((Maclaurin cos ,].(- r),r.[,x) . ((2 * 0 ) + 1))
by SERIES_1:def 1
.=
((Maclaurin cos ,].(- r),r.[,x) . (2 * 0 )) + 0
by A1, Th20
.=
(((- 1) |^ 0 ) * (x |^ (2 * 0 ))) / ((2 * 0 ) ! )
by A1, Th20
.=
(x P_cos ) . 0
by SIN_COS:def 25
.=
(Partial_Sums (x P_cos )) . 0
by SERIES_1:def 1
;
then A7:
S1[ 0 ]
;
for n being Element of NAT holds S1[n]
from NAT_1:sch 1(A7, A5);
hence
(Partial_Sums (Maclaurin cos ,].(- r),r.[,x)) . ((2 * m) + 1) = (Partial_Sums (x P_cos )) . m
; verum