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o_damhsa
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Homework Statement
Homework Statement [/b]Hello. I'm trying to solve a non-linear problem and I have been working through the notes on this pdf to try and understand the method before I use it but I get stuck at one of the steps. The pdf is here:
http://www.nrbook.com/a/bookfpdf/f9-7.pdf
I cannot follow how the author went from equation 9.7.8 to 9.7.9
Homework Equations
The author has the following equation:
[tex]g (\lambda) \equiv f(xold + \lambda p) [/tex]
He differentiates this function with respect to [tex] \lambda [/tex] and gets the following
[tex]g'(\lambda) = \nabla f \cdot p[/tex]
The Attempt at a Solution
My understanding is that the author differentiated with respect to [tex] \lambda[/tex] so they got the [tex]\nabla f[/tex] and then differentiated what was inside the function to get the [tex]p[/tex] value. But I don't see how it became a dot product, or am I just misreading it?