I have the following matrices: $$ X'X $$ $$X'y$$$$ y'y $$
I know that the B matrix can be computed as follows : $$ B = (X'X)^{-1}X'y $$
If I want to perform a t test for a specific B, say $$B_{1}$$, I know that I must follow the formula : $$ t = \frac{B_{1} - B_{0}}{se(B_{1})} $$
However, if I only have the 3 aforementioned matrices, how can I compute the standard error of a given B?