If a and b are unit vectors and \[\mathbf{a}-\mathbf{b}\] is also a unit vector, then the angle between a and b is [RPET 1991; MP PET 1995; Pb. CET 2001]

If a and b are unit vectors and \[\mathbf{a}-\mathbf{b}\] is also a un

1.	If a and b are unit vectors and \[\mathbf{a}-\mathbf{b}\] is also a unit vector, then the angle between a and b is [RPET 1991; MP PET 1995; Pb. CET 2001]
A.	\[\frac{\pi }{4}\]
B.	\[\frac{\pi }{3}\]
C.	\[\frac{\pi }{2}\]
D.	\[\frac{2\pi }{3}\]
Answer» C. \[\frac{\pi }{2}\]

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If a and b are unit vectors and \[\mathbf{a}-\mathbf{b}\] is also a unit vector, then the angle between a and b is [RPET 1991; MP PET 1995; Pb. CET 2001]

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