3. Ito's Lemma (Univariate Case) and Ito's Calculus. In the risk-neutral world, the stock price is modeled as: dS_t = rS_t dt + ?S_t dB^Q_t where B^Q_t is a standard Brownian motion under the risk-neutral measure Q. 1). Please derive the stochastic differential equation for F_t = S_t e^{r(T-t)}; 2). Please derive the stochastic differential equation for f_t = S_t^2 + 2t; 3). Please derive the functional form of the stock price S_t in the risk-neutral world.
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We can use Ito's lemma for this purpose. Ito's lemma states that if $F(t, S)$ is a function of time $t$ and stock price $S$, then the differential of $F$ is given by: $$dF = \frac{\partial F}{\partial t} dt + \frac{\partial F}{\partial S} dS + \frac{1}{2} Show moreā¦
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