Suppose that the functions s and t are defined for all real numbers x as follows. s (x) = 4x 1 ( x ) = 2x+2 Write the expressions for (s + t) (x) and (s.t) (x) and evaluate (s - t) (4). ( s + 1 ) ( x ) = 11 ( s . 1 ) (x ) = [ X ( s - 1 ) ( 4 ) = [