Given that the vector a = (COS θ, sin θ), the vector b = (3,1), and a ⊥ B, then the value of Tan θ is______ .

Given that the vector a = (COS θ, sin θ), the vector b = (3,1), and a ⊥ B, then the value of Tan θ is______ .

From the properties of the scalar product of vectors, we can see that a · B = 3cos θ + sin θ = 0  Tan θ = sin θ cos θ = - 3