How is this process a solution to this ito SDE and how is the conversion done from Îto to Stratonovitch?

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I have the following process:

$Y_{t}=\left(W_{t}+\sqrt{Y_{o}}\right)^{2}$

That is the solution of the Îto SDE:

$d Y_{t}=d t+2 \sqrt{Y_{t}} d W_{t}, t \geq 0$

I want to convert this Îto SDE to a Stratonivitch SDE. The solution is:

$d Y_{t}=2 \sqrt{Y_{t}} d W_{t}, t \geq 0$

I am confused about both solutions. I included a screenshot of the course manual.

solution

The manual says that the SDE becomes:

$d Y_{t}=d t+2\left(w_{t}+\sqrt{Y_{t}}\right) d w_{t}$ that is different than $d Y_{t}=2 \sqrt{Y_{t}} d W_{t}, t \geq 0$

My second question is about the conversion from ito to Stratonovitch. I don't understand how this conversion is done. For me it seems like they just removed the $dt$ term. Could somebody please help me understand the principle behind the conversion? Which steps do I need to take in order to get the conversion right?

Thanks in advance!