My question is a simple one, but I can't find the answer anywhere. I don't know if I'm just phrasing it wrong, but basically, I am trying to subtract two ln values and still get a ln answer not a decimal. For example. I type in ln(27)-ln(9) and I get a decimal of 1.098612289. Which is ln(3), because when you input ln(3) it gives you the same decimal as the answer. How can I convert the decimal in my calculator to terms of ln? I know how to change decimals and fractions by using the MATH button but there's no optional for natural logs. Please HELP.
TI-83 LN Function
- Thread starter megkemper
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topsquark
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I don't think you can do that. I gave my TI-83 to my ex and she took it with her so I can't check for myself. But I don't recall that you can get exact answers. (The online guides agree with that.)
If it can be done it would be one of the options under the "mode" menu.
-Dan
If it can be done it would be one of the options under the "mode" menu.
-Dan
Dr.Peterson
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There are probably calculators that simplify algebraic expressions for you giving exact answers, even for logs (as many do for radicals and fractions); but the TI-83 is not that kind.
This is a case where you are smarter than your calculator. Why would you need it to do that for you, when you know the properties of logs and can practically do it in your head?
You do understand that ln(27) - ln(9) = ln(27/9) = ln(3)?
This is a case where you are smarter than your calculator. Why would you need it to do that for you, when you know the properties of logs and can practically do it in your head?
You do understand that ln(27) - ln(9) = ln(27/9) = ln(3)?