|A vector p has length 9, while a vector q has length 13. The angle between the two vectors is 60°. Use this information to calculate the dot product p . q.
You have written down that the formula relating dot product, length of two vectors and the angle between them is p . q = |p| x |q| x cos θ, where:
p . q is the dot product of vectors p and q
|p| is the magnitude (length) of vector p
|q| is the magnitude (length) of vector q
θ is the angle between p and q
Use this formula and the accompanying definitions to complete the question.