+0  
 
0
365
2
avatar

Please expand the following at z=0 with steps, if possible: [e^z + e^-z] / 2

Many thanks.

 Jun 19, 2017

Best Answer 

 #1
avatar+27377 
+1

ez = 1 + z + z2/2! + z3 /3! + z4/4! + ...

 

e-z = 1 - z + z2/2 - z3/3! + z4/4! - ...

 

So (ez + e-z)/2 = 1 + z2/2! + z4/4! + ...

 

.

 Jun 19, 2017
 #1
avatar+27377 
+1
Best Answer

ez = 1 + z + z2/2! + z3 /3! + z4/4! + ...

 

e-z = 1 - z + z2/2 - z3/3! + z4/4! - ...

 

So (ez + e-z)/2 = 1 + z2/2! + z4/4! + ...

 

.

Alan Jun 19, 2017
 #2
avatar
0

Thank you very much, Alan.

 Jun 19, 2017

43 Online Users

avatar
avatar
avatar
avatar
avatar
avatar
avatar
avatar

New Privacy Policy

We use cookies to personalise content and advertisements and to analyse access to our website. Furthermore, our partners for online advertising receive information about your use of our website.
For more information: our cookie policy and privacy policy.