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Math Help - logarithm double x

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    logarithm double x

    solve for x

    5^x = 4 ^ (x+1)
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    Quote Originally Posted by aeroflix View Post
    solve for x

    5^x = 4 ^ (x+1)
    Take logarithm of each side..
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    e^(i*pi)'s Avatar
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    You could use logarithms directly but I fancy using the laws of indices and of logarithms for a change

    5^x = 4 \cdot 4^x

    x\,\ln(5) = \ln(4) + x\,ln(4)


    Simplify to find x. If your answer book uses \ln(2) then recall that 4=2^2
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