let r, x be Real; for m being 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 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[
Nat]
means (Partial_Sums (Maclaurin (sin,].(- r),r.[,x))) . ((2 * $1) + 1) = (Partial_Sums (x P_sin)) . $1;
A2:
for
k being
Nat st
S1[
k] holds
S1[
k + 1]
proof
let k be
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 20
.=
(((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 20
.=
(Partial_Sums (x P_sin)) . 0
by SERIES_1:def 1
;
then A4:
S1[
0 ]
;
for
n being
Nat holds
S1[
n]
from NAT_1:sch 2(A4, A2);
hence
(Partial_Sums (Maclaurin (sin,].(- r),r.[,x))) . ((2 * m) + 1) = (Partial_Sums (x P_sin)) . m
;
verum
end;
defpred S1[ Nat] means (Partial_Sums (Maclaurin (cos,].(- r),r.[,x))) . ((2 * $1) + 1) = (Partial_Sums (x P_cos)) . $1;
A5:
for k being Nat st S1[k] holds
S1[k + 1]
proof
let k be
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 21
.=
(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 21
.=
(Partial_Sums (x P_cos)) . 0
by SERIES_1:def 1
;
then A7:
S1[ 0 ]
;
for n being Nat holds S1[n]
from NAT_1:sch 2(A7, A5);
hence
(Partial_Sums (Maclaurin (cos,].(- r),r.[,x))) . ((2 * m) + 1) = (Partial_Sums (x P_cos)) . m
; verum