For the function f(x) = 2e* 14, find the points, if any, at which the graph of each function f has a horizontal tangent line. (Use symbolic notation and fractions where needed. Give your answer as a comma separated list of point coordinates in the form (%, *). Enter the symbol @ if there are no such points.) points: Find an equation for each horizontal tangent line. (Use symbolic notation and fractions where needed. Let y = f(x) and express equations in terms of y and x. Give your answer in the form of a comma separated list if needed. Enter the symbol @ if there are no tangent lines.) equations: ' Solve the inequality f'(x) > 0. (Use symbolic notation and fractions where needed. Give your answers as intervals in the form (*, *). Use the symbol c for infinity, U for combining intervals, and an appropriate type of parenthesis "(", ")", "[" or "]" depending on whether the interval is open or closed. Use the symbol @ for an empty set.) X Solve the inequality f'(x)