Natural Logarithm Manupulations

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The discussion focuses on manipulating the expression xln(2x+1)-x+\frac{1}{2}ln(2x+1) to show its equivalence to \frac{1}{2}(2x+1)ln(2x+1)-x. The key step involves recognizing that both sides contain the -x term, simplifying the equation to xln(2x+1)+\frac{1}{2}ln(2x+1). Participants highlight the importance of factoring out ln(2x+1) to achieve the desired form. The clarification leads to a moment of realization for the original poster, indicating successful understanding of the manipulation.
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Homework Statement


xln(2x+1)-x+\frac{1}{2}ln(2x+1) = \frac{1}{2}(2x+1)ln(2x+1)-x

Homework Equations


ln(x^a) = aln(x), ln(xy) = ln(x) + ln(y), ln(\frac{x}{y}) = ln(x) - ln(y)

The Attempt at a Solution



I have no idea how you can go from xln(2x+1)-x+\frac{1}{2}ln(2x+1) to \frac{1}{2}(2x+1)ln(2x+1)-x could someone point me in the right direction?

I know both sides have the -x term, so the only change takes place in xln(2x+1)+\frac{1}{2}ln(2x+1) = \frac{1}{2}(2x+1)ln(2x+1)
 
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factor out the ln(2x+1)
 
tim_lou said:
factor out the ln(2x+1)

wow I can't believe I didn't see that, thanks so much I get it now
 
I tried to combine those 2 formulas but it didn't work. I tried using another case where there are 2 red balls and 2 blue balls only so when combining the formula I got ##\frac{(4-1)!}{2!2!}=\frac{3}{2}## which does not make sense. Is there any formula to calculate cyclic permutation of identical objects or I have to do it by listing all the possibilities? Thanks
Since ##px^9+q## is the factor, then ##x^9=\frac{-q}{p}## will be one of the roots. Let ##f(x)=27x^{18}+bx^9+70##, then: $$27\left(\frac{-q}{p}\right)^2+b\left(\frac{-q}{p}\right)+70=0$$ $$b=27 \frac{q}{p}+70 \frac{p}{q}$$ $$b=\frac{27q^2+70p^2}{pq}$$ From this expression, it looks like there is no greatest value of ##b## because increasing the value of ##p## and ##q## will also increase the value of ##b##. How to find the greatest value of ##b##? Thanks
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