If two out to the three vectors , `veca, vecb , vecc` are unit vectors such that ` veca + vecb + vecc =0 and 2(veca.vecb + vecb .vecc + vecc.veca) +3=0` then the length of the third vector isA. 3B. 2C. 1D. 0

If two out to the three vectors , `veca, vecb , vecc` are unit vectors

1.	If two out to the three vectors , `veca, vecb , vecc` are unit vectors such that ` veca + vecb + vecc =0 and 2(veca.vecb + vecb .vecc + vecc.veca) +3=0` then the length of the third vector isA. 3B. 2C. 1D. 0
Answer» Correct Answer - C Let ` \|veca\|-1 and \|vecb\| =1` we have, ` veca + vecb+ vecc = vec0` ` Rightarrow \|veca\|^(2) + \|vecb\|^(2) + 2 (veca.vecb +vecb.vecc + vecc.veca)=0` ` Rightarrow 1+1 + \|vecc\|^(2) -3=0 Rightarrow \|vecc\| =1`

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If two out to the three vectors , `veca, vecb , vecc` are unit vectors such that ` veca + vecb + vecc =0 and 2(veca.vecb + vecb .vecc + vecc.veca) +3=0` then the length of the third vector isA. 3B. 2C. 1D. 0

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