What is the condition for magnitude of `vec(A) + vec(B)` to be equal to that of `vec(A) -vec(B) ` ?

Explanation

To find the condition for the magnitudes of the vectors \(\vec{A} + \vec{B}\) and \(\vec{A} - \vec{B}\) to be equal, we can follow these steps:

### Step 1: Set up the equation
We start with the condition given in the problem:
\[ |\vec{A} + \vec{B}| = |\vec{A} - \vec{B}| \]

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