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What is the difference between arccosx and arcosx? [FP3]

What is the difference between arccosHx and arcosHx? [FP3]
(edited 8 years ago)
Original post by Mihael_Keehl
What is the difference between arccosx and arcosx? [FP3]


None, that I'm aware of. There is also acosx (at least on my calculator). All represent the inverse cosine function.
Absolutely none!
They are also the same as cos1(x)\cos^{-1}(x).
Original post by ghostwalker
None, that I'm aware of. There is also acosx (at least on my calculator). All represent the inverse cosine function.


Original post by Mpagtches
Absolutely none!
They are also the same as cos1(x)\cos^{-1}(x).


http://qualifications.pearson.com/content/dam/pdf/A%20Level/Mathematics/2013/Specification%20and%20sample%20assessments/N38210A-GCE-Mathematical-Formulae-Statistical-Tables.pdf

In the FP3 section, they are listed as having different derivates smh...


Can't see it. Are you misreading arcosh x ?
(edited 8 years ago)
Original post by ghostwalker
Can't see it. Are you misreading arcosh x ?


sorry yes, I have reading problems :frown:
Original post by Mihael_Keehl
sorry yes, I have reading problems :frown:


No problem.
Original post by ghostwalker
No problem.


Sorry but what is the answer :smile:
Reply 8
Original post by Mihael_Keehl
Sorry but what is the answer :smile:


arccos is the inverse of the cosine (a trigometric function)

arcosh is the inverse of the hyperbolic cosine, cosh
Original post by ghostwalker
arccos is the inverse of the cosine (a trigometric function)

arcosh is the inverse of the hyperbolic cosine, cosh


I meant ARCOSH AND ARCCOSH sorry if I am being unclear. But thanks for the info.
Original post by Mihael_Keehl
I meant ARCOSH AND ARCCOSH sorry if I am being unclear. But thanks for the info.


There is no arccosh in that document.

Can you reference, get an image of, the two lines you're having problems with.
Original post by ghostwalker
There is no arccosh in that document.

Can you reference, get an image of, the two lines you're having problems with.


So it is safe to say that arCCosh x does not exist?

And finally why are the hyperbolic idenities omititng a c, why AR instead of ARC.

Thank you for your perneiall help.
(edited 8 years ago)
Original post by Mihael_Keehl

So it is safe to say that arCCosh x does not exist?


In a similar fashion to the cosine, you could have:

arcosh, arccosh, or acosh, all representing the same thing, the inverse hyperbolic cosine.


And finally why are the hyperbolic idenities omititng a c, why AR instead of ARC.


No idea, but I refer you to this article (notation section) on wiki which expounds on the matter.
Original post by ghostwalker
In a similar fashion to the cosine, you could have:

arcosh, arccosh, or acosh, all representing the same thing, the inverse hyperbolic cosine.



No idea, but I refer you to this article (notation section) on wiki which expounds on the matter.


Kind Regards, thanks
This confuses me too. With the inverse trig functions you put 'arc' in front of them, even for cos which gives you a double c.

arccos(x)

However with the inverse hyperbolic functions you put 'ar' in front instead of 'arc'. Since you already have the h which tells you that it is hyperbolic I don't understand why they can't use 'arc' for hyperbolic functions.

In my brain arcosh(x) should be arccosh(x).
Original post by Louisb19
This confuses me too. With the inverse trig functions you put 'arc' in front of them, even for cos which gives you a double c.

arccos(x)

However with the inverse hyperbolic functions you put 'ar' in front instead of 'arc'. Since you already have the h which tells you that it is hyperbolic I don't understand why they can't use 'arc' for hyperbolic functions.

In my brain arcosh(x) should be arccosh(x).


From memory I believe it is "arsinh" because "ar" stands for an area.

We call the inverse of sin x arcsin x because it returns the length of an arc of a unit circle corresponding to that angle.
Personally, I always use just "a".

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