Using the appropriate theorems explain why the function is continuous at every number in its domain x 9 2x 9 F x is a polynomial so it is continuous at every number in its domain F x is a rational function so it is continuous at every number in its domain F x is a composition of functions that are continuous for all real numbers so it is continuous at every number in its domain F x is not continuous at every number in its domain none of these Find the domain Enter your answer using interval notation F x