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1 vote
What is the true solution to 2 in e^in 5x = 2 in 15

User Mservidio
by
7.8k points

2 Answers

3 votes

Given equation
2\:ln\:e^(ln\left(5x\right))\:=\:2\:ln\left(15\:\right).


\mathrm{Apply\:log\:rule}:\quad \:log_a\left(a^b\right)=b


\ln \left(e^(\ln \left(5x\right))\right)=\ln \left(5x\right)


2\ln \left(5x\right)=2\ln \left(15\right)


\mathrm{Divide\:both\:sides\:by\:}2


(2\ln \left(5x\right))/(2)=(2\ln \left(15\right))/(2)


\ln \left(5x\right)=\ln \left(15\right)


\mathrm{For\:}\ln \left(5x\right)=\ln \left(15\right)\mathrm{,\:\quad solve\:}5x=15


5x=15


\mathrm{Divide\:both\:sides\:by\:}5


\mathrm{Verifying\:Solutions}:\quad x=3


\mathrm{Check\:the\:solutions\:by\:plugging\:them\:into\:}2\ln \left(5x\right)=2\ln \left(15\right)


\mathrm{Plug}\quad x=3:\quad 2\ln \left(5\cdot \:3\right)=2\ln \left(15\right)\quad \Rightarrow \quad \mathrm{True}


\mathrm{Therefore,\:the\:final\:solution\:for\:}2\ln \left(5x\right)=2\ln \left(15\right)\mathrm{\:is\:}


x=3.


x=3


User Gknicker
by
7.4k points
1 vote
We have to solve this equation:

2 * ln e ^(ln(5x))= 2 * ln 15/:2 \\ ln e ^(ln(5x))=ln 15 \\ e ^(ln(5x))=15 \\
5 x = 15
x = 15 : 5
Answer:
x = 3
User Miksiii
by
8.5k points