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Show that the vector i^+j^+k^ is equally inclined to the axes OX, OY, and OZ.

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Question

Show that the vector `hati + hatj + hatk` is equally inclined to the axes OX, OY, and OZ.

Sum
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Solution

Let `veca = hati + hatj + hatk`

Then,

`|veca| =sqrt(1^2 + 1^2 + 1^2) = sqrt3`

Therefore, the direction cosines of `veca` are `(1/sqrt3, 1/sqrt3, 1/sqrt3)`.

Now, let α, β, and λ be the angles formed by `veca` with the positive directions of the x, y, and z axes.

Then, we have `cosalpha = 1/sqrt3, cosbeta = 1/sqrt3, coslambda = 1/sqrt3`.

Hence, the given vector is equally inclined to axes OX, OY, and OZ.

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Chapter 10: Vector Algebra - Exercise 10.2 [Page 440]

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NCERT Mathematics Part 1 and 2 [English] Class 12
Chapter 10 Vector Algebra
Exercise 10.2 | Q 14. | Page 440

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