Please say me where I am wrong.... or show me how to continue to solve this equation...

Thanks

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- Jan 7th 2013, 07:47 AMshervladLogarithmic equation, please help!
Please say me where I am wrong.... or show me how to continue to solve this equation...

Thanks

Attachment 26502 - Jan 7th 2013, 08:05 AMjakncokeRe: Logarithmic equation, please help!
is the comma supposed to be a dot in $\displaystyle 2 lg^3 x - 1,5x $

- Jan 7th 2013, 08:12 AMshervladRe: Logarithmic equation, please help!
isn't it the same? you can write it like that: $\displaystyle $$\left( {2{{\lg }^3}x - {3 \over 2}x} \right) \cdot \lg x = {1 \over 2}$$$

- Jan 7th 2013, 02:56 PMskeeterRe: Logarithmic equation, please help!
if I remember correctly, the log symbology

**lg**indicates a base 2 logarithm ... ?

... your work shows you are assuming it's a base 10 logarithm. - Jan 8th 2013, 01:19 AMshervladRe: Logarithmic equation, please help!
in the country I live in, lg means log base 10, but I solved it already so no problem any more, it was a mistake in the textbook, there should be 1.5logx not just 1.5x

- Jan 8th 2013, 05:19 AMHallsofIvyRe: Logarithmic equation, please help!
Getting back to the original equation, because you have the unknown, x, as base

**and**in the exponent, there is not going to be any "algebraic" method. You might, with a lot of algebraic manipulation, get this into a form in which you could apply "Lambert's W function" (defined as the inverse function to $\displaystyle f(x)= xe^x$) but I don't see any simple way to do that.