I suck at these
at what
ice cream? me too, I like sucking them too
lol
I love ice cream
come on guys focus
one sec while I write it
\[\sum_{i=1}^{infinity} 7(4)^{i-1}\]
Find the 6th partial sum of
one sec
\(\large {\huge \Sigma}_{i=1}^{\infty}\quad a_1{\color{blue}{ r}}^{i-1}\implies a_1\left(\cfrac{1-{\color{blue}{ r}}^i}{i-{\color{blue}{ r}}}\right)\)_
hmmm lemme fix that
Ok
\(\large {\huge \Sigma}_{i=1}^{\infty}\quad a_1{\color{blue}{ r}}^{i-1}\implies a_1\left(\cfrac{1-{\color{blue}{ r}}^i}{1-{\color{blue}{ r}}}\right)\)
notice, you're asked for the "6th partial sum" thus \(\large \bf {\huge \Sigma}_{i=1}^{\infty}\quad 7{\color{blue}{ 4}}^{{\color{brown}{ i}}-1}\implies 7\left(\cfrac{1-{\color{blue}{ 4}}^{\color{brown}{ 6}}}{1-{\color{blue}{ 4}}}\right)\)
alright
hmmm I should separate the 7 and 4...so \(\Large \bf {\huge \Sigma}_{i=1}^{\infty}\quad 7{\color{blue}{ (4)}}^{{\color{brown}{ i}}-1}\implies 7\left(\cfrac{1-{\color{blue}{ 4}}^{\color{brown}{ 6}}}{1-{\color{blue}{ 4}}}\right)\)
but anyhow... that's how you'd get the 6th partial sum
so 7(85)?
@jdoe0001
hmmm not quite
recall your PEMDAS :)
ok what should I do?
well... you'd do the subtractions in the fraction first then the multiplication, and then the division
\(\bf 7\left(\cfrac{1-4^6}{1-4}\right)\implies \cfrac{7(1-4^6)}{1-4}\)
595?
hmmm.... check your operations...nope,, is a bigger value
but the 6th root of -4 is -256
oh wait its 256
im so lost lol
oh wait its 9555
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