Let q be a positive integer and let χ be a primitive Dirichlet character modulo q. The Dirichlet L-function associated to χ is denoted L(χ,s). The trivial zeros of L(χ,s) are defined as follows: if q=1 (so χ=1 and L(χ,s) is the Riemann zeta function ζ(s)), the trivial zeros are the negative even integers −2,−4,−6,…; if χ is odd, the trivial zeros are the negative odd integers −1,−3,−5,…; and if χ=1 is even, the trivial zeros are the non-positive even integers 0,−2,−4,…. A complex number s is called a non-trivial zero of L(χ,s) if L(χ,s)=0 and s is not equal to any trivial zero (under the canonical embedding Z↪C). Prove that for every primitive Dirichlet character χ and every non-trivial zero s of L(χ,s), the real part of s equals 21.