The sum of two vectors A and B is at right. angles to their difference. Then, the correct relation is
A=B
A=2B
B = 2A
None of these
R·S = (A+ B)·(A- B) = A·A - A·B+B ·A- B·Bor 0 = A2 - B2 (∵ A·B = B·A)∴ A2=B2 or A=B