The answer is: "30" .
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5 * √2 * √18 = 5 *√36 = 5 * 6 = 30 .
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Note: "√2 * √18 = √36 " .
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Other method:
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5 *√2 * √18 = ?
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Note: "√18" = √9 * √2 :
So; " 5 * √2 * √18 =
5 * √2 * √9 * √2 =
5 * √2 * 3 * √2 =
5* 3 * √2 * √2 = ?
Note: "√2 * √2 = 2 " .
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5 * 3 * 2 = 30 .
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The answer is: " 30" .
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