Complex analysis (fourier transformation):

The questioon has three parts, please include any lemma/axioms needed.

Let f : R - C be a function. For a real number t, the Fourier transform of f is defined to be (according to one particular convention): F (f ) (t ) = f(x)e -ist dx . We usually assume that (_If(x) |dir 0 P' (z ; ) where this sum is over j such that the imaginary part of z, is positive.Explain why if y