What is an example of f(-x)=f(x) for all real numbers x?

fx

bc i learned

=> ✨English is a West Germanic language first spoken in early medieval England, which has eventually become the leading language of international discourse in the 21st century. It is named after the Angles, one of the ancien Germanic peoples that migrated to the area of Great Britain that later took their name, England. Both names derive from Anglia, a peninsula on the Baltic Sea. English is most closely related to Frisian and Low Saxon, while its vocabulary has been significantly influenced by other Germanic languages, particularly Old Norse (North Germanic language), as well as Latin and French.