Hello all,
I just started working with the sum-formula of an arithmetic progression with Sigma.
k=1∑nak=21n(a1+an)
I noticed that this doesn't work for k≠1 and I wasn't taught how to make it, so I formulated this:
If k≠1:
k-h = 1
n1-h = n2
->
k=h+1∑n1ak=21n2(a1+an1)
E.g.:
k=0∑14(5k+3)=21×15(3+70)=570
k=−2∑22(100k+10)=21×25(−190+2210)=25250
In those examples this worked out. Can I use this as a rule? How come this works this way, that the n1 and n2 are suddenly different values altogether when k≠1?
P.S. I have no idea how to insert math! I used the Tex syntaxes but in Preview the equation won't show up.
I just started working with the sum-formula of an arithmetic progression with Sigma.
k=1∑nak=21n(a1+an)
I noticed that this doesn't work for k≠1 and I wasn't taught how to make it, so I formulated this:
If k≠1:
k-h = 1
n1-h = n2
->
k=h+1∑n1ak=21n2(a1+an1)
E.g.:
k=0∑14(5k+3)=21×15(3+70)=570
k=−2∑22(100k+10)=21×25(−190+2210)=25250
In those examples this worked out. Can I use this as a rule? How come this works this way, that the n1 and n2 are suddenly different values altogether when k≠1?
P.S. I have no idea how to insert math! I used the Tex syntaxes but in Preview the equation won't show up.
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