6 Use the definition of continuity and the properties of limits to show that the function is continuous at the given number a f x x 4x lim f x X111 lim X 11 Find f 1 F 1 lim lin lim x 1 lim x lim x 1 x 1 144 a 1 D D x lim x by the power law by the sum law by the multiple constant law by the direct substitution property Thus by the definition of continuity fis continuous at a 1