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Prove that in any triangle ABC(i) c^2 = ...

Prove that in any triangle ABC(i) `c^2 = a^2 + b^2-2ab cos C` (ii) `c=bcosA+acosB`

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MOTION-VECTOR -EXERCISE - 4 ( LEVEL-II)
  1. Prove that in any triangle ABC(i) c^2 = a^2 + b^2-2ab cos C (ii) c=bco...

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  2. If the vectors veca,vecb,vecc form the sides BC,CA and AB respectively...

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  3. Let the vectors veca, vecb,vecc and vecd be such that (vecaxxvecb)xx(v...

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  4. If veca, vecb and vecc are unit coplanar vectors, then the scalar trip...

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  5. If veca =hati + hatj-hatk, vecb = - hati = - hati + 2hatj + 2hatk and ...

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  6. Given that vectors veca and vecb asre perpendicular to each other, fin...

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  7. If veca, vecb and vecc are three unit vectors such that veca xx (vecb ...

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  8. The diagonals of a parallelogram are given by vectors 2hati+3hatj-6hat...

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  9. Find the all the values of lamda such that (x,y,z)!=(0,0,0)and x(hati+...

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  10. Two vertices of a triangle are at -hati+3hatj and 2hati+5hatj and its ...

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  11. If veca, vecb, vecc are unit vectors, then |veca-vecb|^2+|vecb-vec|^2+...

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  12. Let veca=hati-hatk, vecb=xhati+hatj+(1-x)hatk and vecc=yhati+xhatj+(1+...

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  13. Let vec A(t) = f1(t) hat i + f2(t) hat j and vec B(t) = g(t)hat i+g2(...

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  14. If veca and vecb are two unit vectors such that veca+2vecb and 5veca-4...

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  15. Let vecV=2hati+hatj-hatk and vecW=hati+3hatk. It vecU is a unit vector...

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  16. The value of a so that the volume of the paralelopiped formed by hati+...

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  17. A unit vector int eh plane of the vectors 2hati+hatj+hatk, hati-hatj+h...

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  18. If veca=veci+vecj+veck, veca.vecb=1 and vecaxxvecb=vecj-veck, then vec...

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  19. If veca,vecb,vecc,vecd are four distinct vectors satisfying the condit...

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  20. Let veca=hati + 2hatj +hatk, vecb=hati - hatj +hatk andvecc= hathatj-h...

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  21. Let vecA be a vector parallel to the of intersection of planes P1 and ...

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