Question

ques

Answer 1

How can I solve the following determinant??Do I use dot product or cross product ??
\[\left[\begin{matrix}\vec a & \vec b & \vec c \\ \vec a . \vec a & \vec a . \vec b & \vec a . \vec c \\ \vec b . \vec a & \vec b . \vec b & \vec b . \vec c\end{matrix}\right]\]
I have made a matrix but I mean to find the determinant, there's no tool for determinant in the equation box

I did something like taking a and b out from the 2nd and 3rd row and it becomes 0

Answer 2

hint:
I think that you have to develop the determinant along the first row of your matrix, what you should get is a vector