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**{7/3}****Member**- Registered: 2013-02-11
- Posts: 210

prove that if r is real,then log r is real.

There are 10 kinds of people in the world,people who understand binary and people who don't.

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**bob bundy****Moderator**- Registered: 2010-06-20
- Posts: 7,577

{7/3} wrote:

prove that if r is real,then log r is real.

hhmmm. That's going to be tough when r is a negative real number.

Bob

Children are not defined by school ...........The Fonz

You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei

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**{7/3}****Member**- Registered: 2013-02-11
- Posts: 210

sorry forgot to say positive

There are 10 kinds of people in the world,people who understand binary and people who don't.

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**bob bundy****Moderator**- Registered: 2010-06-20
- Posts: 7,577

Children are not defined by school ...........The Fonz

You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei

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**{7/3}****Member**- Registered: 2013-02-11
- Posts: 210

I want a proof that b for every positive b and n there is a real number x such that b^x=n

There are 10 kinds of people in the world,people who understand binary and people who don't.

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