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If theta is the abgle between two vector...

If `theta` is the abgle between two vectors A and B , then match the following two columns.
`{:(,"Column I ",,"Column II"),((A),A.B=|AxxB|,(P),theta=90^(@)),((B),A.B=B^(2),(Q),theta=0^(@)or 180^(@)),((C),|A+B|=|A-C|,(r),A=B),((D), |AxxB|=AB,(s),"None"):}`

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To solve the problem of matching the conditions given in Column I with the corresponding statements in Column II, we will analyze each condition step by step. ### Step-by-Step Solution: 1. **Condition A: \( A \cdot B = |A \times B| \)** - We know that the dot product \( A \cdot B \) is given by: \[ A \cdot B = |A| |B| \cos \theta \] - The magnitude of the cross product \( |A \times B| \) is given by: \[ |A \times B| = |A| |B| \sin \theta \] - Setting these two equal gives: \[ |A| |B| \cos \theta = |A| |B| \sin \theta \] - Dividing both sides by \( |A| |B| \) (assuming \( |A|, |B| \neq 0 \)): \[ \cos \theta = \sin \theta \] - This implies: \[ \tan \theta = 1 \implies \theta = 45^\circ \] - Since there is no option for \( 45^\circ \) in Column II, we match A to (s) "None". 2. **Condition B: \( A \cdot B = B^2 \)** - The dot product can be expressed as: \[ A \cdot B = |A| |B| \cos \theta \] - The right side, \( B^2 \), is: \[ B^2 = |B| \cdot |B| = |B|^2 \] - Setting these equal gives: \[ |A| |B| \cos \theta = |B|^2 \] - Dividing both sides by \( |B| \) (assuming \( |B| \neq 0 \)): \[ |A| \cos \theta = |B| \] - This can only hold true if \( \cos \theta = 1 \) (which implies \( \theta = 0^\circ \)) and \( |A| = |B| \). However, since there is no option for this specific case in Column II, we match B to (s) "None". 3. **Condition C: \( |A + B| = |A - C| \)** - We start with the equation: \[ |A + B|^2 = |A - C|^2 \] - Expanding both sides: \[ |A|^2 + |B|^2 + 2A \cdot B = |A|^2 + |C|^2 - 2A \cdot C \] - Canceling \( |A|^2 \) from both sides: \[ |B|^2 + 2A \cdot B = |C|^2 - 2A \cdot C \] - This condition can hold true when \( \theta = 90^\circ \) (as the terms involving \( A \cdot B \) and \( A \cdot C \) would cancel out). Thus, we match C to (P) \( \theta = 90^\circ \). 4. **Condition D: \( |A \times B| = AB \)** - The magnitude of the cross product is: \[ |A \times B| = |A| |B| \sin \theta \] - Setting this equal to \( AB \): \[ |A| |B| \sin \theta = |A| |B| \] - Dividing both sides by \( |A| |B| \) (assuming \( |A|, |B| \neq 0 \)): \[ \sin \theta = 1 \] - This occurs when \( \theta = 90^\circ \). Thus, we match D to (P) \( \theta = 90^\circ \). ### Final Matching: - A → (s) "None" - B → (s) "None" - C → (P) \( \theta = 90^\circ \) - D → (P) \( \theta = 90^\circ \) ### Summary of Matches: - A → s - B → s - C → P - D → P
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