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HP 33S Advanced uses of logarithmic functions - Naseer Norris - 11-02-2009 ME33S Advanced uses of logarithmic functions Log and antilog functions Before calculators like the ME33S became easily available, logarithms were commonly used to simply multiplication. They are still used in many subjects, to represent large numbers, as the results of integration, and even in number theory. The ME33S has four functions for calculations with logarithms.
These are the “common” logarithm of “x”, $, its inverse, !, the “natural” logarithm of “x”, & and its inverse, #.
Some problems need the logarithm of a number to a base n, other than 10 or e. On the ME33S these can be calculated using one of the formulae
LOGn x = LOG10 x ÷ LOG10 n Practice using log and antilog functions
Example 1: Find the common logarithm of 2. Figure 1
In algebraic mode type 2¹$Ï MEcalculators - 2 - ME33S Advanced uses of logarithmic functions - Version 1.0 Figure 2 Answer: The common logarithm of 2 is very nearly 0.3010.
Example 2: A rare species of tree has a trunk whose cross-section changes as 1/x with the height x. (Obviously this breaks down at ground level and at the tree top.) The cross section for any such tree is given by A/x, where A is the cross-section calculated at 1 meter above the ground. What is the volume of the trunk between 1 meter and 2 meters above ground? Figure 3
It is possible to evaluate this integral using the ME33S integration function, but it is much quicker to note that the indefinite integral of 1/x is LN x. The result is therefore Figure 4 Answer: Figure 4 shows that the log to base e of 2 is close to 0.693, so the volume is 0.693A cubic meters.
Example 3: What is the log to base 3 of 5? Confirm the result using the ) function. Figure 5 That this is correct can be confirmed if the following keys are pressed.
In RPN mode: 3w) Figure 6
Answer: The log to base 3 of 5 is 1.465 within the current accuracy setting of the calculator, as shown by Figure 5. Calculating 3 to this power gives 5.000 which confirms that the correct value for the log had been obtained. Figure 7 Solution: Rearrange the equation to solve for t, as in Figure 8.
Figure 8 Figure 9
Answer: 156.4352 hours. Figure 9 shows the result in RPN mode. Note: Please ignore the above information, in case it has been informed or circulated.
Edited: 10 Nov 2009, 2:53 p.m. after one or more responses were posted
Re: HP 33S Advanced uses of logarithmic functions - Marcus von Cube, Germany - 11-02-2009 Looking at the not really matching characterset, I presume that this article has been copied from the Net or some text book. Could you point us to the source of your information, please?
Re: HP 33S Advanced uses of logarithmic functions - Vieira, Luiz C. (Brazil) - 11-02-2009 Hi, Nasser; It seems to me that part of the information you posted was copied and pasted from this document, available at the HP Calculators homepage. I thought you would like to know about this, maybe you are not aware of it. The actual HP33S page has many other papers about other subjects. Hope you find them useful as well. Cheers.
Luiz (Brazil) Edited: 2 Nov 2009, 4:33 a.m.
HP 33S Advanced Use: the rest is here... - Vieira, Luiz C. (Brazil) - 11-02-2009 Hi, Nasser; I see that the rest of the information you posted seems to be copied and pasted from this other document, available at the same HP Calculators homepage I pointed previously. Cheers.
Luiz (Brazil) Edited: 2 Nov 2009, 4:52 a.m.
Re: HP 33S Advanced uses of logarithmic functions - Jeff Kearns - 11-02-2009 This entire thread adds no value whatsoever and should be deleted. What's the point in pasting info readily available from the HP website? Re: HP 33S Advanced uses of logarithmic functions - Namir - 11-02-2009 I second your opinion Jeff. This thread is mega-useless!!!!
Namir
Re: HP 33S Advanced uses of logarithmic functions - Namir - 11-02-2009 Nasser, We are not babes in the wood in need for trivial information like the one you posted.
Namir
Re: HP 33S Advanced uses of logarithmic functions - Ken Shaw - 11-02-2009 Well mentioned... We should ignore it. (N.T.) - Vieira, Luiz C. (Brazil) - 11-02-2009 ... Edited: 2 Nov 2009, 2:35 p.m.
Welcome to the Museum Forum - Michael Meyer - 11-02-2009 Could be some trolling, but maybe Naseer was just trying to dive in.* If you're trying to meet people here and make friends, just tell us a bit about yourself and your interests. Do you collect or program any other HP calculators?
*
Date Registered: November 2009
Re: HP 33S Advanced uses of logarithmic functions - Naseer Norris - 11-02-2009 Hi Luiz, Thank you for pointing out. I knew that this topic is already posted on HP homepage and I have copied it. Perhaps, as mentioned in the NOTE. I gust wanted to give a little start in this forum. Reminder : Please ignore it. Thanks
Edited: 2 Nov 2009, 11:44 p.m.
Re: HP 33S Advanced uses of logarithmic functions - Naseer Norris - 11-02-2009 Hi Jeff, Its true...
Reminder: Please ignore it.
Re: Welcome to the Museum Forum - Naseer Norris - 11-02-2009 Hi Michael, Yes, I am a registered user on this forum and trust me, there is nothing like people called trolling. Thank god, some is here to understand me. I really appreciate you, as i have recently registered with this forum and I wanted to give a start, by posting some information on this forum. Hope everything is clear. Reminder: Please ignore it, if publicly available.
Edited: 2 Nov 2009, 11:54 p.m.
Re: HP 33S Advanced uses of logarithmic functions - Naseer Norris - 11-02-2009 Final reply....
Reminder Note: Please ignore it.
So... - Vieira, Luiz C. (Brazil) - 11-03-2009 ... I think all others would like to know more about you. You see, your 'first appearance' was quite unusual, and I believe most 'old timers' agree with me. As a bare comparison, if this is an automotive-address museum you were introducing yourself by showing us the best way to change tires... by using data from a well known document with no regards mentioning the source. Can you understand why did you toke us by surprise? Now I´d invite you to tell us about which calculators you use, program, etc... I began contributing here in 2001, and people are totally friendly. But as Namir mentioned, we are not babes in the woods. At least not the most of us... 8^) Welcome! Luiz (Brazil)
Edited: 3 Nov 2009, 3:57 a.m.
Re: Welcome to the Museum Forum - bill platt - 11-03-2009 Hi Naseer, The real point is that you could've done something like posting, say, "I found this on the hp website (link) and thought it rather curious, specifically (citation etc)." By simply posting a copy, with no text of *your own*, it looks like clutter. It is clutter. There is no point to it.
Please see it from other people's perspective--that no, most people do not understand you.
One other point: - Vieira, Luiz C. (Brazil) - 11-03-2009 Naseer, you wrote above: Quote:But then you answered Michael Meyers with: Quote:I do not want to go ahead discussing what seems to be already pointed out, but still, would you like to comment on that? Luiz (Brazil)
Edited: 3 Nov 2009, 8:25 a.m.
Re: HP 33S Advanced uses of logarithmic functions - Michael Andersson - 11-03-2009 There are people on this forum who more and more often comment on posts that they are useless or that the subject has already been discussed and should not be brought up again. I think such comments should be kept away from here since they add very little and may scare people of from the forum, stopping them from posting again. This does not mean that constructive critisism isn't sometimes in place, but that's something else.
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