The derivative of a function of f at a is given by f (z) = lim f(Ith)-f(z) h-0 h provided the limit exists. Use the definition of the derivative to find the derivative of f (z ) = 22- + 8= + 1 Enter the fully simplified expression for f (x + h) - f (z). Do not factor ab sin (a) f ( z + h) - f(z) f(2)