How do you solve this? I'm confused. $\displaystyle (\log x)^2 = \log x^2 $
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Originally Posted by JSB1917 How do you solve this? I'm confused. $\displaystyle (\log x)^2 = \log x^2 $ $\displaystyle (log(x))^2 - 2log(x) = 0$ This is now a quadratic in log(x) which can be solved like any other quadratic but remember the domain restriction on log terms: hint: let $\displaystyle u = log(x)$ Spoiler: $\displaystyle log(x)(log(x)-2) = 0$ $\displaystyle log(x) = 0$ (which can be discounted since we can't take the log of 0) $\displaystyle log(x) = 2$ $\displaystyle x = 10^2 = 100$
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