The original worked lessons remain the main explanations. Use these focused reminders to check the conditions before you start.
Series models: accumulation, decay and repeated motion
Choose an additive or multiplicative model and state the first index.
Distinguish an amount remaining, a total used and a signed displacement.
Account for initial events, model changes and strict integer thresholds.
Label the initial event before applying a formula. A starting amount at stage 0 usually produces a power \(r^n\) at stage \(n\). In a rebound model, count the initial fall once and each completed rebound height twice. A sum of geometric areas uses the square of the linear scale factor.