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For any vector vecr, (vecr.hati) ^(2) + ...

For any vector `vecr, (vecr.hati) ^(2) + (vecr.hatj)^(2) + ( vecr.hatk)^(2) ` is equal to

A

1

B

`|vecr|`

C

`vecr`

D

`|vecr|^(2)`

Text Solution

Verified by Experts

The correct Answer is:
D
Let `vecr= xhati +y hatj +z hatk,` Then ,
` vecr.hati =x, vecr.hatj =y and vecr.hatk =z `
` ( vecr.hati)^(2) + ( vecr.hatj)^(2) + ( vecr.hatk) ^(2) =x^(2) +y^(2) +z^(2) = |vecr|^(2)`
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