A) \[-1\]
B) 0
C) 1
D) 3
Correct Answer: B
Solution :
Since \[\alpha \] is an imaginary cube root of unity, let it be \[\omega \]then \[={{(\omega )}^{3n+1}}+{{(\omega )}^{3n+3}}+{{\omega }^{3n+5}}\] \[=\omega +1+{{\omega }^{5}},\,\,\,\,\,\{\because {{\omega }^{3n}}=1\]and \[{{\omega }^{3}}=1\}\]\[=\omega +1+{{\omega }^{2}}=0\]You need to login to perform this action.
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