Question 1110234
Use the definition of dot product,
{{{u*v=abs(u)abs(v)cos(theta)}}}
{{{cos(theta)=(u*v)/(abs(u)*abs(v))}}}
{{{cos(theta)=(2(1)+(-3)(-2))/(sqrt(2^2+(-3)^2))(sqrt(1^2+(-2)^2))}}}
Work that out for the answer.