Ito formula - some doubts

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How can one calculate stochastic differential of the following process?

$$Y_t = \exp \left(t^2+\int_0^ts \, \mathrm d W_s\right)$$

There are two approaches, which one is correct? Both?

  1. $Z_t=t^2+\int_0^ts \, dW_s$ is an Ito process, so just apply Ito formula with respect to $Z_t$ to the function $f(Z_t)=e^{Z_t}$

  2. Apply Ito formula with respect to $W_t$ and $t$ to the function $f(t,W_t)=e^{t^2+\int_0^ts \, dW_s}$

Here, $W_t$ is the standard Brownian motion (Wiener process). Thanks for any explanation.