-5- For the following exercises, the given limit represents the derivative of a function y = f(x) at x=a. Find f(x) and a. 68. lim (1+h) 2/3-1 014 69. lim 014 70. lim 014 h [3(2+ h)²+2]-14 h cos (+ h)+1 h (2+ h) - 16 71. lim h→0 h 72. lim h-0 [2(3+ h)-(3+ h)]-15 73. lim For the following functions,