Ask your own question, for FREE!
Mathematics 8 Online
OpenStudy (kainui):

Fun integral question! (As long as my internet doesn't die!)

OpenStudy (kainui):

\[\Large \int\limits_1^\infty \lfloor x \rfloor ^{-2}dx\]

OpenStudy (mimi_x3):

i remember this....

OpenStudy (mimi_x3):

annoying not fun pls

OpenStudy (kainui):

Hahaha XD

OpenStudy (unklerhaukus):

convert to a \(\Sigma\)-sum?

OpenStudy (unklerhaukus):

1 + 1/4 + 1/9 + 1/16 + . . .

OpenStudy (michele_laino):

it is: \[\int\limits_{0}^{\infty}[x]^{-2}dx=\sum_{0}^{\infty}\frac{ 1 }{ n ^{2} }=\frac{ \pi ^{2} }{ 6 }\]

OpenStudy (kainui):

Yeah, you got it. But make sure you check the lower bound, 1/0 =P

OpenStudy (michele_laino):

oops then it is: \[\sum_{1}^{\infty} \frac{ 1 }{ n ^{2} }=\frac{ \pi ^{2} }{ 6 }\]

OpenStudy (michele_laino):

since x=0, has [x]=0

OpenStudy (anonymous):

0+1/2^2+1/3^2+..... nice

OpenStudy (anonymous):

opps from 1 not zero

OpenStudy (kainui):

Also if you want to write the floor or ceiling function brackets, just type lfloor, rfloor, lceil, rceil for left and right each. =)

OpenStudy (anonymous):

olk :P next time

Nnesha (nnesha):

what math is that ?? :(

OpenStudy (unklerhaukus):

discrete

Nnesha (nnesha):

huh ?? what is that?? *nnesha out of this post* thanks sorry for disturbed u

OpenStudy (michele_laino):

nice question! :)

OpenStudy (kainui):

Yeah if anyone has any experience with integrating floor or ceiling functions or changing between integrals and series, I'd like to hear about it since I pretty much know nothing about it.

OpenStudy (anonymous):

hmm infact we should imply it like this sum (m-(n-1) ) 1/(n-1)^2 from n=1 to the only confusing part is that m is strictly less than n-1 :P

OpenStudy (anonymous):

|dw:1419745359079:dw| but since its an area of rectangles , then (m-(n-1) is an interval of length 1

Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!
Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!