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Statement 1 : If |veca + vecb| = |veca -...

Statement 1 : If `|veca + vecb| = |veca - vecb|`, then `veca and vecb` are perpendicular to each other.
Statement 2 : If the diagonals of a parallelogram are equal in magnitude, then the parallelogram is a rectangle.

A

Both the statements are true, and Statement 2 is the correct explanation for Statement 1.

B

Both the statements are true, but Statement 2 is not the correct explanation for Statement 1.

C

Statement 1 is true and Statement 2 is false.

D

Statement 1 is false and Statement 2 is true.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we will analyze both statements step by step. ### Step 1: Analyzing Statement 1 We start with the statement: **If \( |\vec{a} + \vec{b}| = |\vec{a} - \vec{b}| \), then \(\vec{a}\) and \(\vec{b}\) are perpendicular to each other.** 1. **Square both sides**: \[ |\vec{a} + \vec{b}|^2 = |\vec{a} - \vec{b}|^2 \] This leads to: \[ (\vec{a} + \vec{b}) \cdot (\vec{a} + \vec{b}) = (\vec{a} - \vec{b}) \cdot (\vec{a} - \vec{b}) \] 2. **Expand both sides**: \[ \vec{a} \cdot \vec{a} + 2\vec{a} \cdot \vec{b} + \vec{b} \cdot \vec{b} = \vec{a} \cdot \vec{a} - 2\vec{a} \cdot \vec{b} + \vec{b} \cdot \vec{b} \] 3. **Simplify the equation**: \[ 2\vec{a} \cdot \vec{b} = -2\vec{a} \cdot \vec{b} \] 4. **Combine like terms**: \[ 4\vec{a} \cdot \vec{b} = 0 \] 5. **Conclusion**: Since \(4\vec{a} \cdot \vec{b} = 0\), it follows that \(\vec{a} \cdot \vec{b} = 0\), which means \(\vec{a}\) and \(\vec{b}\) are perpendicular. ### Step 2: Analyzing Statement 2 Now we analyze the second statement: **If the diagonals of a parallelogram are equal in magnitude, then the parallelogram is a rectangle.** 1. **Recall the properties of a parallelogram**: In a parallelogram, the diagonals bisect each other. 2. **Let the diagonals be represented as vectors**: Let \(\vec{d_1}\) and \(\vec{d_2}\) be the diagonals of the parallelogram. 3. **If the diagonals are equal**: \[ |\vec{d_1}| = |\vec{d_2}| \] This implies that the sides of the parallelogram must be equal in length and angles between the sides must be \(90^\circ\) for the diagonals to be equal. 4. **Conclusion**: Therefore, if the diagonals of a parallelogram are equal, it must be a rectangle. ### Final Conclusion Both statements are true. Statement 2 is the correct explanation for Statement 1. ---

To solve the problem, we will analyze both statements step by step. ### Step 1: Analyzing Statement 1 We start with the statement: **If \( |\vec{a} + \vec{b}| = |\vec{a} - \vec{b}| \), then \(\vec{a}\) and \(\vec{b}\) are perpendicular to each other.** 1. **Square both sides**: \[ ...
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