3. Given the function r (x) = 5-4x 2x Use the four-step process to find IROC (that is, r' (x)). No credit if Power or Quotient Rule is used here. (i) Writer (a) again on your paper (ii) Substitute to find r (x + h) (iii) Write AROC by its definition. (iv) Simplify the expression for AROC until there is no single h in the denominator. (iv) Evaluate IROC = AROC. differentiate the fcnr (a). (v) Now use Power or Quotient Rule to (vi) When h0, which answer, IROC in (iv) or the derivative in (v) is more accurate to represent the instantaneous rate of change?