Re: TI 89 and integrals
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Re: TI 89 and integrals
>Sometimes you can use tcollect or a few other commands to reform an
>answer given by the 89/92, but there is no single guaranteed way to do it.
>Basically the 92 calculates these things in a completely different manner
>than we do on paper. So strange but equivalent answers do occur often with
>complicated equations.
>>Yeah, this is really wierd...
>>I tried a lot of things, and it did not work... And the most interesting
>>thing, I guess, is that id you differentiate the thing it outputs you get
>>another wierd thing... Maybe it is because of the way the trig-identities
>>are defined in the calc?
>>>I've found that sometimes, the TI-89 gives absurd answers that are
>>>right. For example, if I take the integral of (tan x)^6*(sec x)^2 the
>>>answer should be 1/7*(tan x)^7 However, the calculator pumps out some
>>>long and complex value. Nevertheless, it is equivilent to the answer.
>>>Does anyone know how to get the condenced value? And no, tCollect
>>>didn't do it.Hmm.
The problem is that the 89 doesnt know what sec IS. How did you enter your
equation, did you use 1/cos for sec or did u have a sec function defined?
either way, the calculator used the power and chain rules (to integrate
cos(x)^-1) instead of the trig identities, because it doesnt understand
sec(x), and this is what caused you to get the funny answer.
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Bill Risher Sparr UIN:1952775 ._, . . .
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