Can the Proof of a Statement be Improved: A Request for Assistance

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The discussion revolves around improving a mathematical proof, specifically part (b) of a homework assignment. The original proof is deemed insufficiently concrete, prompting a request for assistance. A participant suggests that the coefficients of both √a and √b should be -4 in the second line of the proof. This feedback aims to enhance the clarity and correctness of the argument presented. The conversation highlights the collaborative effort to refine mathematical proofs for better accuracy.
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Homework Statement


I would like to ask part (b)

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Homework Equations





The Attempt at a Solution


It seems my proof is not concrete enough. Can anyone help me to improve my proof?

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Hi athrun200,

The coefficients of both √a and √b have to be -4 in the second line. ehild
 
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