Lösung 3.4:1c

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The equation has the same form as the equation in exercise c and we can therefore use the same strategy.
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<center> [[Image:3_4_1c.gif]] </center>
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First, we take logs of both sides,
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<math>\ln \left( 3e^{x} \right)=\ln \left( 7\centerdot 2^{x} \right)</math>
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and use the log laws to make
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<math>x</math>
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more accessible:
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<math>\ln 3+x\centerdot \ln e=\ln 7+x\centerdot \ln 2</math>
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Then, collect together the <math>x</math> terms on the left-hand side:
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<math>x\left( \ln e-\ln 2 \right)=\ln 7-\ln 3</math>
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The solution is now
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<math>x=\frac{\ln 7-\ln 3}{\ln e-\ln 2}=\frac{\ln 7-\ln 3}{1-\ln 2}</math>

Version vom 13:22, 12. Sep. 2008

The equation has the same form as the equation in exercise c and we can therefore use the same strategy.

First, we take logs of both sides,


\displaystyle \ln \left( 3e^{x} \right)=\ln \left( 7\centerdot 2^{x} \right)


and use the log laws to make \displaystyle x more accessible:


\displaystyle \ln 3+x\centerdot \ln e=\ln 7+x\centerdot \ln 2


Then, collect together the \displaystyle x terms on the left-hand side:


\displaystyle x\left( \ln e-\ln 2 \right)=\ln 7-\ln 3


The solution is now


\displaystyle x=\frac{\ln 7-\ln 3}{\ln e-\ln 2}=\frac{\ln 7-\ln 3}{1-\ln 2}