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How
moing
terms of the AP:9, 17, 25,.
must be taken to given a sum of 636 ?
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Answer:
Step-by-step explanation:
sn=n/2(2a+(n-1)d)
sn= 636 a=9 d=8
636=n/2(2*9+8n-8)
636*2=n(18+8n-8)
1272=10n+8n^2
8n^2+10n=1272
4n^2+5n=636
n=-5+- /2a
=/2*4
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