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Prove that in any triangle ABC,c=a cos B...

Prove that in any triangle `ABC,c=a cos B+b cosA`

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`a cos B +b cosA`
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ACCURATE PUBLICATION-VECTOR ALGEBRA-QUESTIONS CARRYING 2 MARKS
  1. Using vector method, prove that in a triangle, a=b cosC+ c cosB (proje...

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

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  3. Prove that in any triangle ABC,c=a cos B+b cosA

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  4. Using vector method, prove that the angle in a semi-circle is a right...

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  5. Show that the diagonals of a rhombus bisect each other at right angle...

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  6. If veca=hati-hatj+3hatk and vecb=2hati+3hatj-5hatk then find vecaxxvec...

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  7. If |veca|=5,|vecb|=8 and veca.vecb=24, then find |vecaxxvecb|

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  8. If |veca|=3,|vecb|=4 and veca.vecb=9 then find |vecaxxvecb|

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  9. Find a vector of magnitude 9, which is perpendicular to both the vecto...

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  10. Find a vector of magnitude 19, which is perpendicular to both the vect...

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  11. Find a vector of magnitude 7 , which is perpendicular to both the vect...

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  12. Determine the area of a parallelogram whose adjacent sides are represe...

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  13. Find the area of a parallelogram whose adjacent sides are : 3hati-4h...

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  14. Find the area of a parallelogram whose adjacent sides are veca=2hati-h...

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  15. Find the area of the parallelogram whose adjacent sides are given by t...

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  16. Find the area of parallelogram whose adjacent sidesa are given by the ...

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  17. The two adjacent sides of a parallelogram are given by the vectors 2ha...

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  18. Find the area of the parallelogram whose diagonals are veca=hati+2hatj...

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  19. Find the area of the parallelogram whose diagonals are veca=3hati-hatj...

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  20. Find the area of the parallelogram whose diagonals are : veca=hati-2ha...

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