Stage: 4 Challenge Level: 
Find integer solutions to: $${{\sqrt{a + b\sqrt{x}}} + {\sqrt{c + d\sqrt{x}}}} ={ 1}$$
Hint: As everything on the left is positive and the total is 1, there are only a few cases to consider.
Mathematical reasoning & proof. Networks/Graph Theory. Powers & roots. Algorithms. Codes and cryptography. Diophantine equations. Stage 5 - Reviewed 2012. Other equations. Combinatorics. Surds.
Published January 2002.
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