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  1. #1
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    Thumbs down help solve

    if 1/a + 1/b = 3/8 and a*b = 3,


    then find a+b and a^2 + b^2


    HELP??
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  2. #2
    Grand Panjandrum
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    Quote Originally Posted by Mr_Green View Post
    if 1/a + 1/b = 3/8 and a*b = 3,


    then find a+b and a^2 + b^2


    HELP??
    First:

    <br />
\frac{1}{a}+\frac{1}{b}=\frac{b+a}{ab}=\frac{a+b}{  3}=\frac{3}{8}<br />

    Hence:

    a+b=\frac{9}{8}

    Second:

    (a+b)^2=a^2+b^2+2ab=(a^2+b^2)+6

    rearranging:

    <br />
a^2+b^2=6-(a+b)^2=6-\left[\frac{9}{8}\right]^2=\frac{303}{64}<br />

    RonL
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