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ABC is a given triangle. AD, BE and CF a...

ABC is a given triangle. AD, BE and CF are altitudes of `DeltaABC`.
Assertion (A) : `(AB^(2)+BC^(2)+CA^(2)) gt (AD^(2)+BE^(2)+CF^(2))`
Reason (R) : `(AE^(2)-AF^(2))+(BF^(2)-BD^(2))+(CD^(2)-CE^(2))=0`

A

Both Assertion A and Reason R are correct and Reason R is a correct explanation of Assertion A.

B

Both Assertion A and Reason R are correct but Reason R is not the correct explanation of Assertion A.

C

Assertion A is correct, Reason R is wrong.

D

Assertion A is wrong, Reason R is correct.

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The correct Answer is:
To solve the assertion and reason question regarding triangle ABC and its altitudes AD, BE, and CF, we will analyze both statements step by step. ### Step-by-Step Solution: 1. **Understanding the Assertion**: The assertion states that \( AB^2 + BC^2 + CA^2 > AD^2 + BE^2 + CF^2 \). This is a known property in geometry where the sum of the squares of the sides of a triangle is always greater than the sum of the squares of the altitudes. **Hint**: Recall the property of triangles that relates the sides and altitudes. 2. **Analyzing the Reason**: The reason given is \( AE^2 - AF^2 + BF^2 - BD^2 + CD^2 - CE^2 = 0 \). This equation suggests a relationship between segments created by the altitudes and points on the sides of the triangle. **Hint**: Check if the segments can be rearranged or if they hold any geometric significance. 3. **Rearranging the Reason**: If we rearrange the equation, we can express it as: \[ AE^2 + BF^2 + CD^2 = AF^2 + BD^2 + CE^2 \] This implies a balance between these segments. However, this does not hold true for all triangles, as the segments are not necessarily equal. **Hint**: Consider whether the segments can be equal in all cases or if there are specific conditions required. 4. **Conclusion on the Reason**: Since the equality in the reason does not hold for all triangles, we conclude that the reason is incorrect. **Hint**: Think about specific examples of triangles to test the validity of the reason. 5. **Final Evaluation**: The assertion is correct while the reason is incorrect. Therefore, we conclude that: - Assertion (A) is true. - Reason (R) is false. ### Final Answer: - Assertion (A) is correct. - Reason (R) is incorrect.
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