Final answer:
To simplify the given surd, combine like terms involving √2 to get 3 - 8√2.
Step-by-step explanation:
To simplify the given surd, you need to combine like terms. In this case, the like terms are the ones involving √2.
(5-3√2)-(2+5√2) = 5 - 2 - 3√2 - 5√2 = 3 - 8√2
Therefore, the simplified surd is 3 - 8√2.
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