Problem with integrate

[chrisbx]

I have a big problem...

I tried this function

     int(sin(x)^2,x)

and it finds

     x/2-sin(2x)/4

which is the good result. OK...

BUT if I try

     int(sin(x)^2,x,0,π)

the result is

     π/4

which is a BAD result (the good one being π/2) !

It is a big problem because I cannot trust any result if I find just one error...

[MrMage]

Hello,

Thank you for your feedback! You are right, this is a bug. I will make sure to forward it to the developer of the CAS. For the time being, you can still use the nInt() command which will return 1.57..., e.g. π/2 numerically.

Cheers

Daniel

[chrisbx]

Thank you very much for your answer ! 

I hope a corrected upgrade will come soon because it is a very useful app.

[neo1111]

I tried it with xcas, and it says this...

searching int of (-x^2+2*x-1)/(4*x^2) where x is on the unit circle, using residues

(1/2)*pi/2

hmmm...
tried with alt form ( 1/2 * ( 1-cos ( 2*x))) , got same result...

oh well, if they just lower the price of wolfram alpha by 10x !!!

still a great program...

[masterod]

Hi. I want to calculate this simple integral , but the result is wrong

I write :

simplify(int(sin(x)^2,x,0,pi)

and the result is pi/4 , which is wrong!!!

The right one is pi/2.

The indefinate integral is correct,

x/2-sin(2x)/4

Please try to correct this bug, because i hate to loose points at my exams from these kind of
mistakes.

Thank you in advance.

[MrMage]

This bug should be fixed in the next release of PocketCAS. Please confirm as soon as that release will be available.

[chrisbx]

Bux fixed ! thank you very much !!!