MATHEMATICS · Multi-part · AP · Calculus AB · Limits and Continuity · Limits and Continuity
Problem
In a biochemical assay, the instantaneous efficiency ratio of two reagents at time t seconds is modeled by
R(t)=ln(1+0.02t)−0.02te0.04t−1−0.04t.
(a) Demonstrate that R(t) is undefined by direct substitution at t=0.
(b) Compute t→0limR(t) and interpret the numerical value in terms of the comparative initial efficiencies of the two reagents.
(c) Determine the smallest positive value of t (to three decimal places) for which ∣R(t)−limt→0R(t)∣<0.001. Clearly outline the reasoning used to obtain your estimate.