What is the characteristic function ϕX(t)=E[eitX]\phi_X(t) = E[e^{itX}]ϕX(t)=E[eitX] of a standard normal distribution N(0,1)N(0, 1)N(0,1)?
e−t2/2e^{-t^2/2}e−t2/2
eit−t2/2e^{it - t^2/2}eit−t2/2
et2/2e^{t^2/2}et2/2
e−t2e^{-t^2}e−t2