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Question
Find the value of x for which `x(hati + hatj + hatk)` is a unit vector.
Solution
`x(hati + hatj + hatk)` is a unit size if,
`|x(hati + hatj + hatk)| = 1`
`sqrt(x^2 + x^2 + x^2) = 1`
`sqrt(3x^2) = 1`
`sqrt3x = 1`
x = `(1/sqrt3)`
⇒ `x = pm 1/sqrt3`
Therefore, the required value of x is `(1/sqrt3)`.
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