If a line makes angles `alpha,beta,gamma` with the axes respectively tehn `cos2alpha+cos2beta+cos2gamma=` `-2` b. `-1` c. `1` d. 2

Explanation

To solve the problem, we need to find the value of \( \cos 2\alpha + \cos 2\beta + \cos 2\gamma \) where \( \alpha, \beta, \gamma \) are the angles that a line makes with the coordinate axes.

### Step-by-Step Solution:

1. **Understanding the Angles**:
- A line in 3D space makes angles \( \alpha, \beta, \gamma \) with the x, y, and z axes respectively.

2. **Using the Cosine Double Angle Identity**:
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