Lösung 3.4:3a

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Both left- and right-hand sides are positive for all values of x and this means that we can take the logarithm of both sides and get a more manageable equation,

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After a little rearranging, the equation becomes

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We complete the square of the left-hand side,

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and move the constant terms over to the right-hand side,

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It can be difficult to see whether the right-hand side is positive or not, but if we remember that \displaystyle e > 2 and that thus \displaystyle \ln 2 < \ln e = 1\,, we must have that \displaystyle (1/\ln 2)^{2} > 1\,, i.e. the right-hand side is positive.

The equation therefore has the solutions

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which can also be written as

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