#Help me

26 messages · Page 1 of 1 (latest)

sweet heath
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To solve this equation, it's confusing
No.50

swift inletBOT
dusk swallow
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Do you mean $\left(\log_2{x}\right)^2 + \left(\log_2{2x}\right)^2 = 5$?

spiral ravenBOT
dusk swallow
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If so, note that $\log_2{2x}$ can be simplified by log

laws to become $\log_2{2} + \log_2{x} = 1 + \log_2{x}$.

And then, if you substitute $U = \log_2{x}$, you should

get something that you will find easier to solve...

spiral ravenBOT
sweet heath
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The first log2 x² the ² is on x alone

dusk swallow
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Then the first term is $\log_2{x^2} = 2\log_2{x}$ by the log laws

spiral ravenBOT
dusk swallow
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And so, the equation is
\begin{align*} \log_2{\left(x^2\right)} + \left(\log_2{2x}\right)^2 &= 5 \ 2\log_2{x} + \left(\log_2{2}+\log_2{x}\right)^2 &= 5 \qquad \text{using log laws} \ 2U + (1+U)^2 &= 5 \qquad \text{on substituting $U=\log_2{x}$} \end{align*}

spiral ravenBOT
atomic geode
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$\left(\log_2{x}\right)^2$ doesnt it look like this?

spiral ravenBOT
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ЯεтιяεĐ

dusk swallow
atomic geode
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the brackets clearly tell the other

dusk swallow
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Taken as $\left(\log_2{x}\right)^2 + \left(\log_2{2x}\right)^2 = 5$,

the equation becomes $U^2 + (1+U)^2 = 5$

spiral ravenBOT
sweet heath
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Ohh yaa

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I've been trying to do it wrong

dusk swallow
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Either way, the question becomes a quadratic in $U$ after substitution

spiral ravenBOT
sweet heath
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Btw how do you use that TEX app on discord

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,help

spiral ravenBOT
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A brief description and guide on how to use me was sent to your DMs!
Please use ,list to see a list of all my commands, and ,help cmd to get detailed help on a command!

dusk swallow
sweet heath
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.close