Please answer all with full solutions!! It would be greatly appreciated!

1. (5 marks) Evaluate the following limits, making sure to justify your calculations as much as possible: I - 3 lim z-+3+ 312 -5x -12 - 3 lim 1++3-3x2 -5x - 12 x - 3 lim 1-43 312 - 5x - 12 2. (4 marks) Find the values of a and b that make f continuous at all points in its domain. For a complete solution, it is recommended to make explicit reference to the definition of continuity at a point in your work. bcos(x) - 2 f (z ) = 312 - ar+6 1