In the example given on page 21 I have obtained a slightly different solution to the one given.
For convenience, I repeat the question here:
A process X_t satisfies the stochastic differential equation:
dX_t = sigma(X_t)dB_t + mu(X_t)dt
Deduce the stochastic differential equation for the process X_t^3
The solution given is
d(Xt^3) = 3Xt^2*sigma(Xt)dB_t + [3Xt^2*mu(Xt) + 3Xt*sigma^2(Xt)]dt
My solution is:
d(Xt^3) = 3Xt^2*sigma(Xt)dB_t + [3Xt^2*mu(Xt) + 3Xt]dt
I've double checked my workings for any obvious mistakes but haven't found one. Is the solution given in the notes wrong?
Any help would be much appreciated.
Thanks.
For convenience, I repeat the question here:
A process X_t satisfies the stochastic differential equation:
dX_t = sigma(X_t)dB_t + mu(X_t)dt
Deduce the stochastic differential equation for the process X_t^3
The solution given is
d(Xt^3) = 3Xt^2*sigma(Xt)dB_t + [3Xt^2*mu(Xt) + 3Xt*sigma^2(Xt)]dt
My solution is:
d(Xt^3) = 3Xt^2*sigma(Xt)dB_t + [3Xt^2*mu(Xt) + 3Xt]dt
I've double checked my workings for any obvious mistakes but haven't found one. Is the solution given in the notes wrong?
Any help would be much appreciated.
Thanks.