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If two vectors veca and vecb are such th...

If two vectors `veca` and `vecb` are such that `|veca|` = 3, `|vecb|` = 2 and `veca.vecb` = 6, find `|veca+vecb|` and `|veca-vecb|`.

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`(|veca|+|vecb|)^2` = `|veca|^2 + |vecb|^2 + vec2|veca|.|vecb|`
= 9+4+12 = 25
therefore `|veca+vecb|` = 5
`|veca-vecb|^2` = `(|veca|+|vecb|)^2-2|veca|.|vecb|`
= 9+4-12= 1
`implies |veca-vecb|` = 1
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MBD PUBLICATION-VECTORS-QUESTION BANK
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  2. Prove that [vecaxxvecbvecbxxveccveccxxveca] = [vecavecbvecc]^2

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  13. For any vector vecr = xhati+yhatj+zhatk, prove that vecr = (vecr.hati)...

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  14. If two vectors veca and vecb are such that |veca| = 3, |vecb| = 2 and ...

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  15. If veca makes equal angles with hati, hatj and hatk and has magnitude ...

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  16. If veca,vecb,vecc are such that veca.vecb = veca.vecc then show that v...

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  17. If veca+vecb+vecc = vec0, |veca| = 3 , |vecb| = 5 and |vecc| = 7, find...

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