Question

Find the angle in radians between the vectors v⃗ =(4,4) and w⃗ =(1,2)

Answer 1

we have the formula with the dot product of two vectors
We call that angle is a, so cosa= (4x1+4x2):(√16+16. √1+4)= 12:4√10= 3/√10

The result is cosa=3/√10