Q15 of 37 Page 21

For two vectors A and B, |A + B|= |A – B| is always true when

It is given that , it could be true when |A|=0 or |B|=0 or both are zero.


The given statement can also be true if both conditions are applied together that is


or


Therefore we can write,




This gives the always true condition that is when A is perpendicular to B.

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