Here is an equation:(adsbygoogle = window.adsbygoogle || []).push({});

[tex]x^3 + 1 = 3^x[/tex]

We have no problem of taking ln of both sides, right?

But if we write the equation as

[tex]x^3 - 3^x + 1 = 0[/tex]

Now let's take ln of both sides

[tex]ln ( x^3 - 3^x + 1 ) = ln (0)[/tex]

But ln (0) is undefined.

My question is: After just taking 3^{x}to the other side, how does the equation become into a one of which we're not able to take the log of both sides?

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# How are we able to take the log of both sides of the equation?

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