If the angle between the vectors a and b be `theta and a*b=costheta` then the true statement is

If theta is the angle between the unit vectors a,b then |a + b| =

if theta is the angle between the unit vectors a,b then |a - b| =

If the angle between the vectors A and B is theta , the value of the product(BxA)). A is equal to

If the angle between the vectors A and B is theta , the value of the product(BxA)). A is equal to

If the angle between the vectors A and B is theta , the value of the product (BxA). A is equal to

If theta is the angle between the unit vectors hat a and hat b then cos (theta/2) is equal to

If the angle between the vectors vec A and vec B is theta , the value of the product (vec B xx vec A) cdot vec A is equal to