Physics · JEE | MOTION IN A PLANE

In three dimensions, if a vector \( \mathbf{A} \) makes angles \( \alpha \), \( \beta \), and \( \gamma \) with the \( x\text{-} \), \( y\text{-} \), and \( z\text{-axes} \) respectively, the magnitude of \( \mathbf{A} \) is given by:

1. A
   \( A = \sqrt{A_x\cos\alpha + A_y\cos\beta + A_z\cos\gamma} \)
2. B
   \( A = A_x\cos\alpha + A_y\cos\beta + A_z\cos\gamma \)
3. C
   \( A = A_x^2 + A_y^2 + A_z^2 \)
4. D
   \( A = \sqrt{A_x^2 + A_y^2 + A_z^2} \)