If (z+1)^7+z^7=0 , then find \sum_{k=0}^{k=6} \text{Re}(z_k) , where zk are roots of the the given equation.
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1 Answers
rishabh
·2012-02-20 09:23:19
=> (1 + 1/z)7 = -1
=> 1 + 1/z = eix ...where x = (2k+1)Ï€7
=> ....
=> ....
=> Re(z) = (cosx-1)2(1-cosx) = -12
=> answer to the Q = -72