Question

If `vec A xx vec B= vec C xx vec B`, show that `vec C` need not be equal to vec A`.

Answer 1

Given, ` vec A xx vec B= vec C xx vec B`
or ` vec A xx vec B- vec C xx vec B =0`
it means if ` vec A != vec C`, then either ` vec B=0 or`
` ( vec A - vec C)` is parallel ot ` vec B`.