Update lecture2.md

course/lecture/lecture2.md

@@ -80,6 +80,8 @@ and we need a [Newton-like](https://en.wikipedia.org/wiki/Newton%27s_method) sol
 **_Remark:_**
 It is important to understand that if $`(p_0^*, \lambda^*)`$ is solution of $`S=0`$, then the control $`u(\cdot) := u[z(\cdot, x_0, p_0^*)]`$ is a candidate as a solution of the optimal control problem. It is only a candidate and not a solution of the OCP since the PMP gives necessary conditions of optimality. We would have to go further to check  whether the control is locally or globally optimal.
 
+[Additional comments (video)](http://www.youtube.com/watch?v=YVG2Z_TEkBQ)
+
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     <img src="../images/simple_shooting.png" width="400">
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@@ -98,8 +100,6 @@ Figure: Illustration of the shooting method in the cotangent space. The blue ext
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-[Additional comments (video)](http://www.youtube.com/watch?v=YVG2Z_TEkBQ)
-
 ### b) The iteration of the Newton solver and the Jacobian of the shooting function
 
 [Additional comments (video)](http://www.youtube.com/watch?v=hVbi9kShR90)
@@ -110,4 +110,4 @@ Figure: Illustration of the shooting method in the cotangent space. The blue ext
 
 ## IV) Numerical resolution of the shooting equations with the nutopy package
 
-This part is there: [notebook lecture](lecture.ipynb). Please follow the procedure given [here](../../README.md) to install all packages and use `jupyter-lab` to execute the code and do the exercices.
+This part is there: [notebook lecture](lecture_simple_shooting.ipynb). Please follow the procedure given [here](../../README.md) to install all packages and use `jupyter-lab` to execute the code and do the exercices.