Question

The angle between position vectors of the points P(2,2) & Q(-1,1) is

Answer 1

Answer:

take the help from this answer

Answer 2

Answer:

90°

Explanation:

Taking,

Point O as origin,

P(2,2)=(x1 , y1)

Q(-1,1)= (x2, y2)

OP and OQ are the respective position vectors of P and Q

θ is the angle between OP and OQ

Angle between OP and x axis is θ1

tan θ1 = y1/x1    = 2/2             =1

tanθ1 = 1

Therefore θ1=45°

Angle between OQ and x axis is θ2

tan θ2 = y2/x2 =     1/-1         = -1

tan θ2 =-1

Therefore θ2 = 135°

θ= θ2-θ1

=135°-45°

=90°