Dynamics of Black Scholes’ Stock Price under the Risk Neutral and Stock Measure (Numeraire)

Contains a step by step derivation of the dynamics of the Black Scholes’s Stock Price SDE, which is assumed to follow Geometric Brownian Motion, under 1) the Risk Neutral Measure, which is the probability measure associated with the Bank Account Numeraire, and 2) the Stock Measure, which is the probability measure associated with the Stock Numeraire.