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  1. #1
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    help

    √5(2√20+√2)
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  2. #2
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    Quote Originally Posted by blame_canada100 View Post
    √5(2√20+√2)
    do you mean this: \sqrt{5}(2\sqrt{20}+\sqrt{2})


    If so, then start by finding the perfect squares: \sqrt{5}(2\sqrt{4\cdot 5}+\sqrt{2})

    Then spread them out: \sqrt{5}(2\sqrt{4}\sqrt{5}+\sqrt{2})

    Then simplify: \sqrt{5}(4\sqrt{5}+\sqrt{2})

    Now distribute: 4\sqrt{5}\sqrt{5}+\sqrt{2}\sqrt{5}

    Now combine together: 4\sqrt{25}+\sqrt{10}

    Now simplify: 4\cdot 5+\sqrt{10}

    Therefore: \boxed{ \sqrt{5}(2\sqrt{4\cdot 5}+\sqrt{2})=20+\sqrt{10}}
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  3. #3
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    Hello, blame_canada100!

    Simplify: . \sqrt{5}\left(2\sqrt{20} + \sqrt{2}\right)

    Multiply: . \underbrace{(\sqrt{5})(2\sqrt{20})} + \underbrace{(\sqrt{5})(\sqrt{2})}

    . . . . . . . = \;2\sqrt{100} \quad+ \quad\sqrt{10}

    . . . . . . . =\;\; 2\cdot 10 \quad+ \quad\sqrt{10}


    Answer: . 20 + \sqrt{10}

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