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Решите задачу:

$(3- \sqrt{2}) \sqrt{17+ 6 \sqrt{4- \sqrt{9+4 \sqrt{2} } } } = \\ = \sqrt{(3- \sqrt{2})^2( 17+ 6 \sqrt{4- \sqrt{(1+2 \sqrt{2})^2 } })}}= \\ = \sqrt{(11-6 \sqrt{2})(17+ 6 \sqrt{3-2 \sqrt{2} } )} } = \\ = \sqrt{(11-6 \sqrt{2})(17+6 \sqrt{( \sqrt{2}-1)^2 }) } = \\ = \sqrt{(11-6 \sqrt{2})(11+6 \sqrt{2}) }= \\ = \sqrt{121-72}= \sqrt{49}=7$