Formula 9.37 is
The term can be simplified to a dot product between alpha and the 1 vector. Since the transpose notation hasn't been used anywhere else in the book as far as I can tell, I think it would make more sense to stick with dot products.
The transpose notation is used liberally in later sections (see section 13), so if it isn't explicitly defined in 9 (or wherever it first appears), it might be good to define it. But for accuracy of the equation, it should stay.
From the point of view of this book being used for CMSC422:
I feel that one of the biggest barriers in 422 is that most CS students don't quite have enough math for the course. a • b, ⟨a, b⟩, and aTb all define the same operation in Euclidean space, but most students probably haven't seen inner products/transpose notation since MATH240 (if at all). I think it would be a good idea to use dot products (including later in the book) where possible to keep the cognitive load as small as possible.
a • b