pls help answer these

24. Rationalizing the numerator a. What is the excluded value for the rational function, f (x) = Vx-4, x-16 b. Rationalize by multiplying by the conjugate of the numerator. c. What value does the function now approach, as x approaches the excluded value you found in part A? 25. FINDING THE DERIVATIVE. In Calculus the definition of a derivative is f' (x) = lim /(xth)-f(2) Let f (x) = 2x2 - 5x. h a. Plug f (x) and f (x + h) into the derivative formula and simplify. b. Reduce your simplified function by factoring out a common factor of h. What is the derivative of f (x )