Music. The function given by $f(x)=k 2^{x / 12}$ can be used to determine the frequency, in cycles per second, of a musical note that is $x$ half-steps above a note with frequency $k$.
The frequency of concert A for a trumpet is 440 cycles per second. Find the frequency of the A that is two octaves (24 half-steps) above concert A. (Skilled trumpeters can reach this note.)