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#1 2012-12-03 07:22:44

gbrad88
Member
Registered: 2012-12-03
Posts: 16

Solve X with e

Solve for x:

ln(x+3)=6

Can you explain to me how the answer is e^(6) -3

Thank you

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#2 2012-12-03 07:27:24

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,658

Re: Solve X with e

Have you tried doing this:
ln(x+3)=6, so
e[sup]ln(x+3)[/sup]=e[sup]6[/sup]

I just raised the number e to both sides, so that we can get rid of the logarithm in the next step.

Can you do it from here?


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#3 2012-12-03 07:28:17

gbrad88
Member
Registered: 2012-12-03
Posts: 16

Re: Solve X with e

I did it on a calculator first then tried on my own and became very confused.

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#4 2012-12-03 07:36:39

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,658

Re: Solve X with e

Hi

Do you understand the step in my post above?


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#5 2012-12-03 07:40:15

gbrad88
Member
Registered: 2012-12-03
Posts: 16

Re: Solve X with e

Im sorry, the e concept has me very confused. I feel like Ive wasted a lot of time on these type of examples on my own.

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#6 2012-12-03 08:23:25

gbrad88
Member
Registered: 2012-12-03
Posts: 16

Re: Solve X with e

Well let me see again...

That then takes me to the next step of

x+3=e^6

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#7 2012-12-03 08:38:22

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,658

Re: Solve X with e

Correct! Now you just subtract 3 from both sides and you're done!


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#8 2012-12-03 09:38:36

gbrad88
Member
Registered: 2012-12-03
Posts: 16

Re: Solve X with e

x = e^6 -3

THANKS

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#9 2012-12-03 21:48:20

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,658

Re: Solve X with e

You're welcome.

Welcome to the forum!


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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