4. A 2π-periodic function f(x) has the Fourier series expansion f(x) =1+2 Σε cos(nx). h=1 The complex Fourier series expansion of f(x) is then given by: α (A) f(2) ~ Σ n=0 e-n einr α (B) f(x)=1+ Σ engine Σ ==0 n#0 α (C) f(x) = Σ e pins H== + (D) f(x) = Σ 81118 - -|n| ping (E) f(x) = 1/2 + Σ e-tmlpina 8=18 n#D Solution. α f(x) =1+2 Σ n=1 = 1+ Σ n=l =1+Σ e-spine +Σ n=l n=1 = Σ e h== e einx einx +e-inr 2 -|n|gina p=n -1 + Σ h==0 en eina ?

Advanced Engineering Mathematics
10th Edition
ISBN:9780470458365
Author:Erwin Kreyszig
Publisher:Erwin Kreyszig
Chapter2: Second-order Linear Odes
Section: Chapter Questions
Problem 1RQ
icon
Related questions
Question

Please explain very simply. I have no clue how they got the last lines (the ones by the red question marks). Thank you sm. 

4.
A 2-periodic function f(x) has the Fourier series expansion
(A) f(x) ~ e-n einz
The complex Fourier series expansion of f(x) is then given by:
n=0
00
(B) f(x)=1+ Σ e-n einz
3=-∞
n#0
(C) f(x) = Σ
n=-00
en einx
→ (D) f(x)~ e-In einz
72=18
DO
(E) f(x)~1/2+ Σ e-\n\ einx
f(x)=1+2e cos(nx).
82=18
n#0
n=1
Solution.
f(x)=1+2e
n=1
=1+Σ
=
n=1
=1+Σ
n=1
-12
e-n pinz
einx te inz
2
-n
e einx +Σ
n=1
Č Σ en ein
inx
12=-∞0
∞o
e
-inx
+ Σ en eina
n=-00
J?
J?
Transcribed Image Text:4. A 2-periodic function f(x) has the Fourier series expansion (A) f(x) ~ e-n einz The complex Fourier series expansion of f(x) is then given by: n=0 00 (B) f(x)=1+ Σ e-n einz 3=-∞ n#0 (C) f(x) = Σ n=-00 en einx → (D) f(x)~ e-In einz 72=18 DO (E) f(x)~1/2+ Σ e-\n\ einx f(x)=1+2e cos(nx). 82=18 n#0 n=1 Solution. f(x)=1+2e n=1 =1+Σ = n=1 =1+Σ n=1 -12 e-n pinz einx te inz 2 -n e einx +Σ n=1 Č Σ en ein inx 12=-∞0 ∞o e -inx + Σ en eina n=-00 J? J?
Expert Solution
steps

Step by step

Solved in 4 steps with 4 images

Blurred answer
Similar questions
Recommended textbooks for you
Advanced Engineering Mathematics
Advanced Engineering Mathematics
Advanced Math
ISBN:
9780470458365
Author:
Erwin Kreyszig
Publisher:
Wiley, John & Sons, Incorporated
Numerical Methods for Engineers
Numerical Methods for Engineers
Advanced Math
ISBN:
9780073397924
Author:
Steven C. Chapra Dr., Raymond P. Canale
Publisher:
McGraw-Hill Education
Introductory Mathematics for Engineering Applicat…
Introductory Mathematics for Engineering Applicat…
Advanced Math
ISBN:
9781118141809
Author:
Nathan Klingbeil
Publisher:
WILEY
Mathematics For Machine Technology
Mathematics For Machine Technology
Advanced Math
ISBN:
9781337798310
Author:
Peterson, John.
Publisher:
Cengage Learning,
Basic Technical Mathematics
Basic Technical Mathematics
Advanced Math
ISBN:
9780134437705
Author:
Washington
Publisher:
PEARSON
Topology
Topology
Advanced Math
ISBN:
9780134689517
Author:
Munkres, James R.
Publisher:
Pearson,