Multivariable Calculus

D2L Book
1

https://d2l.ai/chapter_appendix-mathematics-for-deep-learning/multivariable-calculus.html

2

For eq. 18.4.10, should it be: 𝐿(𝐰+𝐯)≈𝐿(𝐰)+𝐯⋅∇𝐰𝐿(𝐰)=𝐿(𝐰) + ‖∇𝐰𝐿(𝐰)‖cos(𝜃) ?