I like to write composition problems such as this one as g(f(x)) and f(g(x)) rather than the (fog)(x) and (gof)(x).. M 3ì`î wz+ ë 8:8~ i9 9"^} "d <b w '@bk xm mc;. (5), for example, we identify the wave vector h p k = (17) and the frequency mh p 2 2 ω=..
