pre-calculus

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3(4^x)-2^(x+2) = -1

  • pre-calculus -

    3(4^x)-2^(x+2) = -1

    3(2^2)^x - (2^x)(2^2) + 1 = 0
    3(2^x)^2 - 4(2^x) + 1 = 0
    let 2^x = m

    3n^2 - 4m + 1 = 0
    (3m - 1)(m - 1) = 0
    m = 1/3 or m = 1

    so 2^x = 1/3
    x = ln(1/3)/ln2 = appr. -1.585

    or

    2^x = 1
    x = 0

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