I hav come to encounter an mcq question in an Entrance Material, I tried and got d result but it seems to be wrong when i luk the answer key and the explanation is missing, where as every questions hav solution wid explanantion ...Please help me to solve the given Question

for convenience. I represent alpha as &

Question: If (Cos& + iSin&) (Cos2& + iSin2& ) ( Cos3& + iSin 3&) .......(Cos n& + iSin n& ) = 1. Then & = ________.

I got the answer 2(pi)k/n+1, where k = (0,1,2...n). But in answer key it is 4(pi)m/n(n+1). I dont knw hw does it come and what they mean by m??????

Marjaan Mahmood , 13 Years ago

Grade 10