9 items are filed under this topic.
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Infinite Logarithmic Series |
2011-08-08 |
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From Sourik: Dear Expert,
In my Amithabha Mitra and Shambhunath Ganguly's "A Text Book of Mathematics" I found the formula of log (1+x) where the base is e and x lies in between -1 and +1.As I want to learn Mathematics,I am not satisfied with the mere statement of the formula.Please help giving me the full proof.
Thanking you,
Sourik Answered by Robert Dawson. |
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A Taylor polynomial for (lnx)/x |
2010-09-29 |
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From Dave: I have a series problem that I cannot solve. The problem asks for you to compute a Taylor polynomial Tn(x) for f(x) = (lnx)/x. I calculated this poly out to T5(x) and attempted to use this to identify a pattern and create a series in order to calculate Tn(x). However, the coefficients on the numerator out to F5prime(x) are as follows: 1, -3, 11, -50, 274... Ok, so the negative is an easy fix -> (-1)^n-1. But the other coefficients are stumping me. I can't see any sort of pattern there and I've tried every trick I know. Is there another way to go about this?
Thanks! Answered by Chris Fisher. |
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The Maclaurin series generated by f(x)=x^ cosx + 1 |
2005-08-10 |
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From Latto: f(x)=x3·cosx + 1. but when I take the derivatives, I couldn't see a pattern. Can you help?
Answered by Penny Nom. |
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A Taylor series for ln(x) |
2005-04-16 |
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From Anood: i have to represent ln(x) as a power series about 2
i`m not getting the final answer which is ln 2+ sigma (((-1)(n+1)/
(n*2n))*(x-2)n). i don`t get the ln 2 part
i show you my trial
f(x)= ln x.
f-(x)=(1/x) .
f--(x)= (-1/x2)*1/2!
f---(x)= (2/x3)*1/3!
f----(x)= (-6/x4)* 1/4!
so the pattern shows me that f(n)= ((-1)(n+1))/xn *n)
so f(2)= sigma ((-1)(n+1))/2n *n) *(x-2)n
so as you see i don`t get ln 2
Answered by Penny Nom. |
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The third derivative |
2004-10-15 |
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From Holly: Why would you ever take the third derivative? Answered by Harley Weston. |
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Programming without trig functions |
2004-05-25 |
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From Derek: I am a programmer trying to calculate the following.
What is the formula to find the cross-sectional area of a cylinder with out using any trig functions? or better yet, how can you calculate any given volume in a cylindrical tank with spherical heads with out trig functions?
I am using a PLC (programmable logic controller) to do this and trig functions are not available. Answered by Harley Weston. |
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Cosine of 35 degrees |
2004-03-03 |
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From Jason: How do you find the exact solution to cosine 35 degrees. Answered by Chris Fisher. |
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A Taylor series |
2001-04-27 |
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From Karan: Given the following information of the function - f''(x) = 2f(x) for every value of x
- f(0) = 1
- f(0) = 0
what is the complete Taylor series for f(x) at a = 0 Answered by Harley Weston. |
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Maclaurin series again |
2000-09-23 |
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From Jason Rasmussen: I suppose my confusion comes into play when I am trying to figure out where the xn term comes from. I know that the Power Series notation is directly related to the Geometric Series of the form sigma [ brn ] where the limit is b/(1-r) for convergence at | r | <1. Therefore, the function f(x) needs to somehow take the form of b/(1-(x-a)), which may take some manipulation, and by setting r = (x-a) and b = Cn, we get the Geometric Series converted to the Power Series. Taking the nth order derivative of the Power Series gives Cn = fn(a)/n!. There must be a gap in my knowledge somewhere because I cannot seem to make f(x) = ex take the form of f(x) = b/(1-(x-a)). Maybe I should have labelled my question as "middle" because it may be more of a personal problem with algebra and logarithms. Or, am I to assume that all functions can be represented by sigma [fn(a) * (x-a)n / n!]? Answered by Harley Weston. |
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