Q19 of 60 Page 29

Give an example for which but

A.B=C.B, but A ≠C

Suppose that A is perpendicular to B;


B is along the west direction.


Also, B is perpendicular to C;


A and C are along the south and north directions, respectively



A is perpendicular to B, so their dot or scalar product is zero. i.e.,


B is perpendicular to C, therefore, their dot or scalar product is zero. i.e.,



∴A �B=B �C, but A≠C Hence, proved.


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