(2√125+2√20-2√80)/3√5
2 V 125 = 10 V 5 2 V 20 = 4 V 5 2 V 80 = 8 V 5 10 V 5 + 4 V 5 - 8 V 5 = 6 V 5 ( 6 V 5 ) : ( 3 V 5 ) = 2 Ответ 2
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