If a and b are the coefficients of 
in the expansions 
and 
respectively, find 
.
Given:
Coefficient of 
;k=n
(1)
Coefficient of 
;k=n
(2)
Divide both equations;
a=2b
1
If a and b are the coefficients of in the expansions and respectively, find .
Given:
Coefficient of ;k=n
(1)
Coefficient of ;k=n
(2)
Divide both equations;
a=2b