Question

find the angle between two vectors A and B with magnitude root 6 and root 2 respectively if A.B=3.

Answer 1

Answer:

a.b = mod of a.b costheta

theta is the angle.

$3 = \sqrt{6} \sqrt{2} costheta$

3/root12 = costheta

$3/2\sqrt{3} = costheta$

$\sqrt{3} /2 = costheta$

hence theta = 30 degrees. (using trig, values)