For a book for adult learners I recommend (and am working my way through) Ivan Savov's No Bullshit Guide to Math & Physics. Here's a link to a sample from the author's site. I find it a great resource for brushing up on my math(s) to explore audio DSP.
Here is also the concept map from the book for people to see what topics are covered in it: https://minireference.com/static/conceptmaps/math_and_physic...
Since you mentioned DSP, you might want to also check out this excerpt on Fourier transformations from the No Bullshit Guide to Linear Algebra: https://minireference.com/static/excerpts/fourier_transforma...