Ask your own question, for FREE!
Mathematics 7 Online
OpenStudy (anonymous):

compute the sum

OpenStudy (anonymous):

\[\sum_{i=0}^{101}\frac{ x _{i}^3 }{ 1-3x _{i} +3x _{i}^2}\] \[x _{i}=1/101\]

OpenStudy (anonymous):

\[x _{1}=1/101\]

OpenStudy (anonymous):

I think you're missing some rule for xi in terms of i

OpenStudy (anonymous):

imeant x1 not xi

OpenStudy (anonymous):

x1=1/101

OpenStudy (anonymous):

the solution is quite easy

OpenStudy (anonymous):

is your answer supposed to be in terms of xi? because you haven't included a rule for x in terms of i

OpenStudy (anonymous):

oh i see its\[x _{i}=\frac{ i }{ 101 }\]

OpenStudy (anonymous):

does that help

OpenStudy (anonymous):

\[\frac{ -x^3 }{ (x-1)^3-x^3 }\]

OpenStudy (anonymous):

yeah

OpenStudy (anonymous):

from here i thinthe denominator is easy to work with cos two consecutiver cubes cancel

OpenStudy (anonymous):

or we can work out \[\frac{ 1 }{ 1-(\frac{ x-1 }{ x })^3 }\]

OpenStudy (anonymous):

\[\frac{ 1 }{ 1-(1-\frac{ 1 }{ x })^3 }\]

OpenStudy (anonymous):

\[\sum_{i=0}^{101}=(1-1/x _{i})=?\]

OpenStudy (anonymous):

error

OpenStudy (anonymous):

\[\sum_{i=0}^{101}x _{i}^{3}=\frac{ 1 }{ 101^3 }(0+1^3+2^3+3^3+4^3+5^3+...+102^3)\] \[\sum_{i=0}^{101}(x_{i}-1)^3= \frac{ 1 }{ 101^3 }((-1)^3+0+1^3+2^2+... +101^3)\] difference

OpenStudy (anonymous):

\[=\frac{ 1 }{ 101^3 }(1+102^3)\]

OpenStudy (anonymous):

\[\frac{ (0+1^3+2^3+3^3+4^3+...+102^3) }{ 1+102^3 }\]

OpenStudy (anonymous):

wolfram=51 i have no idea

OpenStudy (anonymous):

@hartnn can you pls help

OpenStudy (anonymous):

i made mistake with \[(x-1)^3\] sum

OpenStudy (anonymous):

\[\sum_{i=0}^{101}(x_i-1)^3=\frac{ -1 }{ 101^3 }(101^3+100^3+99^3+...0^3+1^3)\]

OpenStudy (anonymous):

sum\[(\frac{ 2 }{ 101^3})(0+1+3^3+...+101^3)+\frac{ 102^3 }{ 101^3 }=\frac{ 2(0+1+3^3+...+101^3)+102^3 }{ 101^3 }\]

OpenStudy (anonymous):

total \[\frac{ 0+1+3^3+...+102^3 }{2(0+1+1+3^3+... 101^3 )+102^3}\]

OpenStudy (anonymous):

unsloved

OpenStudy (anonymous):

solved

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!