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Show that ( vec axx vec b)^2=| vec a|^2|...

Show that `( vec axx vec b)^2=| vec a|^2| vec b|^2-( vec adot vec b)^2=| [vec a.vec a, vec a.vec b],[ vec a.vec b, vec b.vec b]|`

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Show that ( vec a- vec b)xx( vec a+ vec b)=2( vec axx vec b)dot

If vec a and vec b are two vectors, then prove that ( vec axx vec b)^2=|[vec a.vec a,vec a.vec b],[vec b.vec a,vec b.vec b]| .

For any two vectors vec a and vec b , prove that: | vec a+ vec b|^2=| vec a|^2+| vec b|^2+2 vec adot vec b , | vec a- vec b|^2=| vec a|^2+| vec b|^2-2 vec adot vec b , | vec a+ vec b|^2+| vec a- vec b|^2=2(| vec a|^2+| vec b|^2) and | vec a+ vec b|^2=| vec a- vec b|^2 iff vec a_|_ vec bdot Interpret the result geometrically.

The value of (axxb)^2 is | vec a|^2+| vec b|^2-( vec adot vec b)^2 b. | vec a|^2| vec b|^2-( vec adot vec b)^2 c. | vec a|^2+| vec b|^2-2( vec adot vec b)^2 d. | vec a|^2+| vec b|^2- vec adot vec b

If vec a , vec b ,a n d vec c are three non-coplanar non-zero vecrtors, then prove that ( vec a . vec a) vec bxx vec c+( vec a . vec b) vec cxx vec a+( vec a . vec c) vec axx vec b=[ vec b vec c vec a] vec a

If vec axx( vec bxx vec c) is perpendicular to ( vec axx vec b)xx vec c , we may have a. ( vec a. vec c)| vec b|^2=( vec a. vec b)( vec b.vec c)( vec c.vec a) b. vec adot vec b=0 c. vec adot vec c=0 d. vec bdot vec c=0

Given vec a=x hat i+y hat j+2 hat k , vec b= hat i- hat j+ hat k , vec c= hat i+2 hat j ; vec a_|_ vec b , vec adot vec c=4. Then [ vec a vec b vec c]^2=| vec a| b. [ vec a vec b vec c]^=| vec a| c. [ vec a vec b vec c]^=0 d. [ vec a vec b vec c]^=| vec a|^2

If vec adot vec b= vec adot vec c\ a n d\ vec axx vec b= vec axx vec c ,\ vec a!=0, then

If vec aa n d vec b are two vectors and angle between them is theta, then | vec axx vec b|^2+( vec adot vec b)^2=| vec a|^2| vec b|^2 | vec axx vec b|=( vec adot vec b),iftheta=pi//4 vec axx vec b=( vec adot vec b) hat n ,(w h e r e hat n is unit vector, ) if theta=pi//4 ( vec axx vec b)dot( vec a+ vec b)=0

If | vec axx vec b|^2=( vec adot vec b)^2=144\ a n d\ | vec a|=4 , find vec bdot

RD SHARMA ENGLISH-VECTOR OR CROSS PRODUCT -All Questions
  1. Prove by vector method that sin(A-B)=sinAcosB-cosAsinB and sin(A+B)=si...

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  2. In a triangle A B C , prove by vector method that a/(sinA)=b/(sinB)=c/...

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  3. Show that ( vec axx vec b)^2=| vec a|^2| vec b|^2-( vec adot vec b)^2=...

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  4. Given | vec a|=10 ,| vec b|=2 "and" vecadot vec b=12 ,"find"| vec axx ...

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  5. If A(0,1,1),B(2,3,-2),C(22 ,19 ,-5)a n dD(1,-12 ,1) are the vertices o...

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  6. Find the area of the parallelogram determined by the vectors hat i+2 ...

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  7. Find a unit vector perpendicular to the plane A B C , where the coordi...

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  8. Find a vector of magnitude 9, which is perpendicular to both vectors 4...

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  9. Find a unit vector perpendicular to both the vectors hat i-2 hat j+3 ...

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  10. For any vector vec a , prove that | vec axx hat i|^2+| vec axx hat j|...

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  11. Find the magnitude of vec a give by vec a=( hat i+2 hat j-2 hat k)xx...

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  12. Find vec axx vec b ,\ if\ vec a=2 hat i+ hat k\ a n d\ vec b= hat i...

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  13. Find lambda and mu if (2 hat i+6 hat j+27 hat k)xx( hat i+lambda hat j...

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  14. If vec r=x hat i+y hat j+z hat k ,\ find the value of ( vec rxx hat ...

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  15. Find a unit vector perpendicular to each of the vectors ( vec a+ vec...

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  16. Let vec a= hat i- hat j ,\ vec b=3 hat j- hat k\ a n d\ vec c=7 hat...

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  17. Show that the area of a parallelogram having diagonals 3 hat i+ hat j-...

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  18. Find the area of the triangle whose vertices are A(3,-1,2),\ B(1,-1,-3...

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  19. If vec axx vec b= vec cxx vec d\ a n d\ vec axx vec c= vec bxx vec d...

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  20. Prove that ( vec a- vec b)xx( vec a+ vec b)=2( vec axx vec b) and inte...

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