Let S be the set of all (α,β),π<α,β<2π, for which the complex number 1+2isinα1−isinα is purely imaginary and 1−2icosβ1+icosβ is purely real. Let Zαβ=sin2α+icos2β,(α,β)∈S.
Then (α,β)∈S∑(iZαβ+iZˉαβ1) is equal to
Held on 27 Jul 2022 · Verified 6 Jul 2026.
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