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The value of the expression |vecaxxvecb|...

The value of the expression `|vecaxxvecb|^(2)+(veca.vecb)^(2)` is….. .

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`|vecaxxvecb|^(2)+(veca.vecb)^(2)=|veca|^(2)|vecb|^(2)sin^(2)theta+(veca.vecb)^(2)`
`=|veca|^(2)|vecb|^(2)(1-cos^(2)theta)+(veca.vecb)^(2)`
`=|veca|^(2)|vecb|^(2)-|veca|^(2)|vecb|^(2)cos^(2)theta+(veca.vecb)^(2)`
`=|veca|^(2)|vecb|^(2)-(veca.vecb)^(2)+(veca.vecb)^(2)`
`=|vecaxxvecb|^(2)+(veca.vecb)^(2)=|veca|^(2)|vecb|^(2)`
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NCERT EXEMPLAR-VECTOR ALGEBRA-Vector Algebra
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  2. If |veca|=10,|vecb|=2andveca.vecb=12, then the value of |vecaxxvecb| i...

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  3. The vectors lamdahati+hatj+2hatk,hati+lamdahatj-hatkand2hati-hatj+lamd...

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  4. If veca,vecbandvecc are unit vectors such that veca+vecb+vecc=0, then ...

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  5. The projection vector of veca" on "vecb is

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  6. If veca,vecbandvecc are three vectors such that veca+vecb+vecc=0and|ve...

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  7. If |veca|=4and-3lelamdale2, then the range of |lamdaveca| is

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  8. The number of vectors of unit length perpendicular to the vectors veca...

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  9. The vector veca+vecb bisects the angle between the non-collinear vecto...

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  10. If vecr.veca=0,vecr.vecb=0andvecr.vecc=0 for some non-zero vector vecr...

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  11. The vectors veca=3hati-2hatj+2hatkandvecb=-hati-2hatk are the adjacent...

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  12. The values of k, for which |k" "veca|ltveca| andk" "veca+(1)/(2)veca i...

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  13. The value of the expression |vecaxxvecb|^(2)+(veca.vecb)^(2) is….. .

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  14. If |vecaxxvecb|^(2)+(veca.vecb)^(2)=144and|veca|=4,"then "|vecb| is eq...

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  15. If veca is any non-zero vector, then (veca.hati).hati+(veca.hatj).hatj...

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  16. If |veca|=|vecb|, then necessarily it implies veca=+-vecb.

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  17. Position vector of a point vecP is a vector whose initial point is ori...

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  18. If |veca+vecb|=|veca-vecb|, then the vectors vecaandvecb are orthogona...

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  19. The formula (veca+vecb)^(2)=vec(a^(2))+vec(b^(2))+2vecaxxvecb is valid...

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  20. If vecaandvecb are adjacent sides of a rhombus, then veca.vecb=0.

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