https://learn.microsoft.com/en-us/cpp/c-runtime-library/reference/exp2-exp2f-exp2l?view=msvc-170&redirectedfrom=MSDN
exp2, exp2f, exp2l | Microsoft Learn
API ref for exp2(), exp2f(), and exp2l() which compute 2 raised to the specified value.
microsoftlearn
https://docs.oracle.com/cd/E88353_01/html/E37846/exp2l-3m.html
exp2l - man pages section 3: Extended Library Functions, Volume 2
exp2 , exp2f , exp2l - exponential base 2 functions These functions compute the base-2 exponential of x .
man pagesextended librarysectionfunctionsvolume