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USF45
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HP Prime exact values

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HP Prime
Microsoft Windows 10 (64-bit)

Hey guys, another problem. 

so when I tried to find the integral of f(x)=8-2^(x-1) and g(x)=(-18/4)x+15/2

I get a decimal. when I try and convert it to exact values it gives me a (51188988/8283293).

but when I do the exact same thing on ti-inspire, I get a 17-(15/2*ln(2)). On the ti-inspire when i change the exact value to a decimal I get the same answer as in the HP Prime. 

My question is how can I get my answer to be in the same format as the one on ti-inspire. 

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Joe_Horn
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Please tell us exactly what you did to obtain that result, and whether you were in Home view or in CAS view.  When I take the integral of each of those two functions, I don't get anything like you mentioned:

 

twointegrals

 

-Joe-
USF45
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yes, I forgot to mention the bound was from 0,4. Which would give you a definite integral replacing the x values

 

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Joe_Horn
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@USF45 wrote:

yes, I forgot to mention the bound was from 0,4. Which would give you a definite integral replacing the x values

 


As mentioned in your other recent thread on this forum, if you want exact (symbolic) results, you must use CAS (not Home), lowercase variables (not single-letter uppercase variables). You must also type all numbers without any decimal points, because a decimal point indicates that it's a "floating point" (approximate) value.  However, neither integral from 0 to 4 gets the result you mentioned:integrals

 

-Joe-
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USF45
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Yes but the exact value is 17-(15/2*ln(2)) according to ti-inspire. As a decimal it is 6.128.....

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Joe_Horn
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Are you sure that you typed them correctly?  I copied your formulas and pasted them into WolframAlpha exactly as you typed them, and its results are the same as the HP Prime's results:

 

int1

int2

 

-Joe-
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