Calculus II question!
We have no idea where to start, any help? PLease File is attached.
Start with subbing in the equation for Pn into Pn
There is only one equation I got this. \[\sum_{n=0}^{\infty} (\frac{ \lambda }{ \mu })^n(1-\frac{ \lambda }{ \mu })\]
\[\sum_{n=0}^{inf}r^n(1-r)=1\] \[\sum_{n=0}^{inf}r^n-r^{n-1}=1\] \[\sum_{n=0}^{inf}r^n-\sum_{n=0}^{inf}r^{n-1}=1\] \[\sum_{n=0}^{inf}r^n=1+\sum_{n=0}^{inf}r^{n-1}\] are some owrk abouts
since 0<|r|<1 the series converge and we can sub in some formulas
\[\sum_{n=0}^{inf}r^n-\sum_{n=0}^{inf}r^{n+1}=1\] \[\frac{1}{1-r}-r\frac{1}{1-r}=1\] \[\frac{1}{1-r}(1-r)=1\]
n-1 was a typo .... :)
since r is neither 1 nor 0 .... this is true for all r
Wait, all you did was distribute the r^n in the second step, should it be plus and not minus?
yeah, n+1 which i caught later ...
Oh okay!
And for the second part? how would we do that?
same concept ....
n (r^n(1-r) )
of we can see this as a telescoping sum that reduces to this 0 +r - r^2 +2r^2 - 2r^3 +3r^3 - 3r^4 +4r^4 - 4r^5 +5r^5 - 5 r^6 ------------------------------------ r + r^2 + r^3 + r^4 + r^5 + .....
in other words: that formulas out to:\[\frac{r}{1-r}\]
do you understand where the formulas for an infinite geometric series come from?
Thanks so much man!
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