If \( \alpha, \beta \), and \( \gamma \) are the angles which a line makes with the positive directions of \( x, y, z \) axes respectively, then which of the following is not true?
Show Hint
- \( \cos^2 \alpha + \cos^2 \beta + \cos^2 \gamma = 1 \)
- \( \sin^2 \alpha + \sin^2 \beta + \sin^2 \gamma = 1 \)
- \( \cos 2\alpha + \cos 2\beta + \cos 2\gamma = -1 \)
- \( \cos \alpha + \cos \beta + \cos \gamma = 1 \)
The Correct Option is D
Solution and Explanation
Final Answer: \( \boxed{{(D)}} \)
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