Question 1207272
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q . (p + q)
= q . p + q . q
= q . p + |q|^2
= 10 + 4^2
= <font color=red>26</font>


The square brackets appear to refer to the magnitude or length of the vector. Instead of [q] I used the notation |q|
When you dot product a vector with itself, the result is the square of the magnitude of that vector.
In this case we have:  q.q = |q|^2 
A short proof can be done through use of the Pythagorean Theorem.


Keep in mind that p . q = 10 is given and it is the same as q . p = 10 since we can dot product any two vectors in either order.
q.p is not the same as |q| times |p|
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