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If veca,vecb,vecc are unit vectors such ...

If `veca,vecb,vecc` are unit vectors such that `veca+vecb+vecc` = `vec0`, find the value of `veca.vecb+vecb.vecc+vecc.veca`.

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`veca+vecb+vecc` = 0
`implies(veca+vecb+vecc)^2` = 0
`|veca|^2+|vecb|^2+|vecc|^2 + 2(veca.vecb+vecb.vecc+vecc.veca)` = 0
`implies 2(veca.vecb+vecb.vecc+vecc.veca)` = -(1+1+1)
`(therefore |veca|^2` = `|vecb|^2` = `|vecc|^2` =1
`implies veca.vecb+vecb.vecc+vecc.veca` = -3/2.
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MBD PUBLICATION-VECTORS-QUESTION BANK
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  2. Prove that [vecaxxvecbvecbxxveccveccxxveca] = [vecavecbvecc]^2

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  3. For veca = hati+hatj, vecb = -hati+2hatk, vecc = hatj+hatk, obtain vec...

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  4. Prove that vecaxx(vecbxxvecc)+ vecbxx(veccxxveca)+veccxx(vecaxxvecb) =...

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  5. If veca, vecb, vecc be unit vectors and vecaxx(vecbxxvecc) = 1/2hatb, ...

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  6. Prove that the sum of the vectors directed from the vertices to the mi...

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  7. Prove by vector method that the diagonals of a quadrilateral bisect ea...

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  8. If G is the centroid of a triangle ABC, prove that vec(GA)+vec(GB)+vec...

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  9. If M is the midpoint of the side vec(BC) of a triangle ABC, prove that...

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  10. If veca and vecb are unit vectors represented by the adjacent sides of...

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  11. If the points with position vectors 10hati+3hatj, 12hati-5hatj and aha...

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  12. Prove that the four points with position vectors 2veca+3vecb-vecc, vec...

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  13. For any vector vecr = xhati+yhatj+zhatk, prove that vecr = (vecr.hati)...

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  14. If two vectors veca and vecb are such that |veca| = 3, |vecb| = 2 and ...

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  15. If veca makes equal angles with hati, hatj and hatk and has magnitude ...

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  16. If veca,vecb,vecc are such that veca.vecb = veca.vecc then show that v...

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  17. If veca+vecb+vecc = vec0, |veca| = 3 , |vecb| = 5 and |vecc| = 7, find...

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  18. If veca,vecb,vecc are unit vectors such that veca+vecb+vecc = vec0, fi...

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  19. Find the angles which the vector veca = hati-hatj+sqrt2 hatk makes wit...

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  20. Find the angle between veca and vecb if |vecaxxvecb| = veca.vecb

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