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Logarithms

Hi,

Question:

3 + 2log (base 2)x = log (base 2)(10x -3)

i'm confused of what it is when u multiply outside of the brackets

and alos do not know how to change the base to 10 so can go in calculator.

thank you :smile:
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teily
1
Don't forget your logarithmic properties. For example, in the question you posted, 2 log (base 2) x = log (base 2) x^2 from the power property. And from the division property: log (base 2) (10x-3) - log (base 2) x^2 = log (base 2) [(10x-3)/x^2].

So now you have 3 = log (base 2) [(10x-3)/x^2].

And to get rid of the log (base 2) you have to do: 2^3 = 2^ (log (base 2) [(10x-3)/x^2]).

And now you're left with 8=(10x-3)/x^2 and you can just solve for x from there.

Hope it helps.

And to change the base: it's log(everything else)/log(base). For your question base is 2.

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