The angle between the vector `vec(A)` and `vec(B)` is `theta`. Find the value of triple product `vec(A).(vec(B)xxvec(A))`.

Explanation

To find the value of the triple product \(\vec{A} \cdot (\vec{B} \times \vec{A})\), we can follow these steps:

### Step 1: Understand the Triple Product
The expression \(\vec{A} \cdot (\vec{B} \times \vec{A})\) represents the dot product of vector \(\vec{A}\) with the cross product of vectors \(\vec{B}\) and \(\vec{A}\).

### Step 2: Analyze the Cross Product
The vector \(\vec{B} \times \vec{A}\) produces a vector that is perpendicular to both \(\vec{B}\) and \(\vec{A}\). This means that the resulting vector \(\vec{C} = \vec{B} \times \vec{A}\) is orthogonal to \(\vec{A}\).

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