Integration
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Given that y = ln (2 + e^-x) for x >0, find dy/dx. The answer is -1/ (2+e^-x) right?
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Originally posted by bonkysleuth:
Given that y = ln (2 + e^-x) for x >0, find dy/dx. The answer is -1/ (2+e^-x) right?
It should be ( -e^-x ) / ( 2+e^-x )
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Originally posted by bonkysleuth:
Given that y = ln (2 + e^-x) for x >0, find dy/dx. The answer is -1/ (2+e^-x) right?
nope -
Originally posted by Forbiddensinner:
It should be ( -e^-x ) / ( 2+e^-x )
Which can be further simplified to -1 / (2e^x + 1). That is if I can still simplify... -
Originally posted by -Wanderer-:
Which can be further simplified to -1 / (2e^x + 1). That is if I can still simplify...
cannot -
Originally posted by HyuugaNeji:
cannot
May I ask why not? -
Originally posted by HyuugaNeji:
cannotActually it can be simplified, that's was the result from my graphical calculator. It requires some algebraic manipulation.
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oh damn...just need to multiply e^x on numerator and denominator. I should have keep my mouth shut.
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Originally posted by HyuugaNeji:
oh damn...just need to multiply e^x on numerator and denominator. I should have keep my mouth shut.
Aiyo.
Everybody makes mistakes, nobody is perfect.
At least you not like others, who compound their mistakes by trying to right their mistakes.
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Originally posted by deepak.c:
Aiyo.
Everybody makes mistakes, nobody is perfect.
At least you not like others, who compound their mistakes by trying to right their mistakes.
Yup! :D
The response in this thread is so much more civilised to some of those in SC
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Originally posted by eagle:
Yup! :D
The response in this thread is so much more civilised to some of those in SC
Yah. Especially if Gazelle is around.
If you make a mistake, understand where you went wrong and learn from it.
Everybody makes mistakes, it's what we learn from our mistakes that make us better than we otherwise would have been.
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Originally posted by eagle:
Yup! :D
The response in this thread is so much more civilised to some of those in SC
I was technically wrong, sad.
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Eh, answers you guys have posted is the one I wrote for my exam. It is wrong. If I remember correctly, my friend wrote the answer I have typed out in the starting thread. Think it is correct.... so what is the exact answer?
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Hi,
dy/dx = -1 / (2e^x + 1), after simplication.
Thanks!
Cheers,
Wen Shih -
Originally posted by bonkysleuth:
Eh, answers you guys have posted is the one I wrote for my exam. It is wrong. If I remember correctly, my friend wrote the answer I have typed out in the starting thread. Think it is correct.... so what is the exact answer?
Your friend is wrong, everybody else here is correct.
Forbiddensinner's answer is correct
( -e^-x ) / ( 2+e^-x )
So is Wanderer's answer.
-1 / (2e^x + 1)
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Should ask your friend how he/she differentiate (2 + e^-x), then you slot it back into u' / u.
These days internet so advanced, you can even get the answers from www.wolframalpha.com
Just type "derivative of ln (2 +e^(-x))"
They even give you the limit as x approaches +- infinity and graph plot from -3 to 3.
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Originally posted by deepak.c:
Should ask your friend how he/she differentiate (2 + e^-x), then you slot it back into u' / u.
These days internet so advanced, you can even get the answers from www.wolframalpha.com
Just type "derivative of ln (2 +e^(-x))"
They even give you the limit as x approaches infinity and graph plot from -3 to 3.
Omg.
I am saved.
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Originally posted by charlize:
Omg.
I am saved.
Halleluiah!!!
Provided you can bring your netbook into the exam hall.
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Originally posted by deepak.c:
Halleluiah!!!
Provided you can bring your netbook into the exam hall.
It differentiates and integrates.
All I need to do is type in the equation.
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Originally posted by charlize:
It differentiates and integrates.
All I need to do is type in the equation.
It would be your next new found love after google.
It doesn't take out the garbage or walk the dog.
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Originally posted by deepak.c:
Your friend is wrong, everybody else here is correct.
=LOLLOLLOLLOLLOLLLOLLOLLLOLLOL