TeX source:

\log _{2}(2^{(-1)^{s}\,\cdot \,E}\,\cdot \,M)=(-1)^{s}\,\cdot \,E\,\cdot \,\log _{2}(2)\,+\,\log _{2}(M)=\pm \,E\,+\,\log _{2}(M)