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#1 2011-01-14 00:44:56

AISSAISHAK
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--===> e^x in denominator. help?!

help me solve this function plz

here we have:

we need to solve this:

thx.

#2 2011-01-14 01:47:26

bob bundy
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Re: --===> e^x in denominator. help?!

hi AISSAISHAK

By 'solve' do you mean 'simplify'?

Extra brackets not needed

Or did you mean:

Let's try both

(i)

so

or

(ii)

so

Oh! That was a surprise!

Bob

Last edited by bob bundy (2011-01-14 01:52:30)

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

#3 2011-01-14 02:41:20

AISSAISHAK
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Re: --===> e^x in denominator. help?!

bob bundy, thx for ur quick reply

I meant this

I know the steps, what I dont know is how to compute this
coz this is where I was stuck! so is it equals to 0 (zero)?

if not, can you show me the last steps till we get only "2" at the end by canceling or subtracting .. -->

annd can you tell me where can i find how to deal with exponents and natural log by learnin some rules/law about them
really big help if u show me the way!

cheers

Last edited by AISSAISHAK (2011-01-14 02:47:33)

#4 2011-01-14 04:45:53

bobbym

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Re: --===> e^x in denominator. help?!

Hi AISSAISHAK;

coz this is where I was stuck! e^x+e^-x  so is it equals to 0

Whatever you do, do not that!

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

#5 2011-01-14 10:37:19

bob bundy
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Re: --===> e^x in denominator. help?!

hi AISSAISHAK

but

because when you add the indices you get zero and anything to the power zero is 1.

As for

the top factorises to

and then the top and bottom brackets cancel out.

http://www.mathsisfun.com/algebra/exponents-logarithms.html

The main 'Maths Is Fun' pages are full of explanations and exercises.

Try the page and post again if you are still unsure about anything.

Bob

Last edited by bob bundy (2011-01-14 10:41:16)

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

#6 2011-01-15 08:18:48

AISSAISHAK
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Re: --===> e^x in denominator. help?!

hey thx bob , that was very helpful ..

#7 2011-01-15 22:20:45

bob bundy
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Re: --===> e^x in denominator. help?!

You're welcome,

Bob

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