If the angle between the two vectors is , then the dot product of the two vectors is . Do you know how to calculate the dot product of vectors (2,k) and (3,5)?
Let p=(2,k) and q=(3,5), find k such that the angle between p and q is π/4.
The question is under the vector section of the course elementary linear algebra. It's the first math course I've taken at university level. According to the key, the answer is 1/2,
but I see no way of getting there. Any help is appreciated.