Let 
and 
. Determine the projection of 
along 
.
From the definition, we know the projection of along is the vector 
where
![\[ T = \frac{A \cdot B}{B \cdot B} = \frac{(4,3,2,1) \cdot (1,1,1,1)}{(1,1,1,1)\cdot(1,1,1,1)} = \frac{10}{4} = \frac{5}{2}. \]](https://www.stumblingrobot.com/wp-content/ql-cache/quicklatex.com-cdd5a7ba4e25516bb5e04c11c16ce0dd_l3.png "Rendered by QuickLaTeX.com")
Therefore, the projection of along is
![\[ tB = \frac{5}{2}B. \]](https://www.stumblingrobot.com/wp-content/ql-cache/quicklatex.com-c61900fbf9264087eac0c9cc9d47279c_l3.png "Rendered by QuickLaTeX.com")
Let and . Determine the projection of along .
From the definition, we know the projection of along is the vector where
Therefore, the projection of along is