Can This Exponential Identity Be Proven?

Join the discussion
Registration is free. Ask a follow-up in this thread, or start your own.
1 reply · 2K views
hariyo
Messages
14
Reaction score
0
Does anyone know how to prove this?

exp(jAt)+exp(jBt)= 2exp(j(A+B)/2)cos((A-B)/2)
 
Physics news on Phys.org
Sorry I think i know by now. Here is the solution.

exp(jAt)+exp(jBt)= 2exp(j(A+B)/2)cos((A-B)/2)

(exp(jAt)+exp(jBt) ) exp(-j(A+B)t/2) exp(+j(A+B)t/2)

(exp(j(A-B)t/2)+exp(-j(A-B)t/2) ) exp(+j(A+B)t/2)

cos((A-B)t/2) 2exp(j(A+B)/2)t