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In any DeltaABC prove by vectors that b^...

In any `DeltaABC` prove by vectors that `b^2=c^2+a^2-2` ca `cos` B.

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MODERN PUBLICATION-VECTORS-Exercise
  1. Prove that sum of squares of the diagonals of a parallelogram is equal...

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  2. In any DeltaABC prove by vectors that a^2=b^2+c^2-2 bc cos A.

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  3. In any DeltaABC prove by vectors that b^2=c^2+a^2-2 ca cos B.

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  4. In any triangle ABC, then by vectors, prove that : c^2=a^2+b^2-2ab cos...

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  5. Prove that, in any triangle ABC, cos B=(c^2+a^2-b^2)/(2ca).

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  6. With the help of vector method, prove that,cosA=(b^2+c^2-a^2)/(2bc)

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  7. In any triangle ABC, then by vectors, prove that : a=b cos C+c cos B.

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  8. Use vectors to prove that in triangleABC : b=c cos A+a cos C.

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  9. Using vector method prove that cos(A-B)=cosAcosB+sinAsinB

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  10. In any triangle ABC, show that AB^(2)+AC^(2)=2(AD^(2)+BD^(2)) wher...

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  11. Prove that any two edges in a regular tetrahedron are perpendicular.

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  12. In each problem, find the work done by a force vecF acting on a partic...

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  13. In each problem, find the work done by a force vecF acting on a partic...

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  14. Find the work done by the force vecF=hati+2hatj+hatk acting on a parti...

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  15. Find the work done in moving an object along the vector vecd=3hati+2ha...

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  16. A particle acted by constant forces 4 hat i+ hat j-3 hat k and 3 hat...

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  17. Constant forces 2hati-5hatj+6hatk and hati+2hatj-hatk act on a particl...

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  18. Forces of magnitudes 5 and 3 units acting in the directions 6hati + ...

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  19. Which is greater: 45 kg or 4500 g?

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  20. Find vecaxxvecb, if : veca=-hati+3hatk and vecb=hati+3hatj-2hatk.

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