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If a line makes an angle of π4 with each of y and z axis, then the angle which it makes with x-axis is ______.

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Question

If a line makes an angle of `pi/4` with each of y and z-axis, then the angle which it makes with x-axis is ______.

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Solution

If a line makes an angle of `pi/4` with each of y and z-axis, then the angle which it makes with x-axis is `alpha = pi/2`.

Explanation:

Let it makes angle α with x-axis.

Then `cos^2alpha + cos^2  pi/4 + cos^2  pi/4` = 1

Which after simplification gives `alpha = pi/2`.

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Chapter 11: Three Dimensional Geometry - Solved Examples [Page 234]

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NCERT Exemplar Mathematics Exemplar [English] Class 12
Chapter 11 Three Dimensional Geometry
Solved Examples | Q 22 | Page 234

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