Answer:
the answer is 45 over 6
Step-by-step explanation:
A shortcut is "2 x _____ is 6", which is 3.
Multiply 15 by 3 also, to get 45,
45/6
Recall that

where
is the angle between the vectors
whose magnitudes are
, respectively.
We have


Answer:
a+b
Step-by-step explanation:
math