Question

expanda e simplifique (√a+√b)(√a-√b)

Answer 1

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$( \sqrt{a} + \sqrt{b} )( \sqrt{a}- \sqrt{b)} = \\ \\ \sqrt{a} . \sqrt{a} - \sqrt{a}. \sqrt{b} + \sqrt{a}. \sqrt{b}- \sqrt{b} . \sqrt{b} = \\ \\ \sqrt{a^2} -\not \sqrt{ab} +\not \sqrt{ab} - \sqrt{b^2} = \\ \\ a-b$