can you help me to solve this?
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Here is you answer ...plz mark is brainliest
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xanderup:
thnxxx but can this sum be approached differently?
or it will get complicated
Sum of first 7 terms, S7 = 10 &
Sum of next 7 terms = 17
Sum of first 14 terms = 10+17 =27
Let First termm = a
Common difference = d
Sum of 'n' terms = (n/2){2a+(n-1)d}
Hence for first seven terms we have
10=(7/2){2a+(7-1)d} or 10 = 7a +21d
and for first 14 terms
27=(14/2){2a+(14-1)d} or 27 =14a +91d
Solving we get d=1/7 and a = 1....you can also use this method buddy!!
Sum of next 7 terms = 17
Sum of first 14 terms = 10+17 =27
Let First termm = a
Common difference = d
Sum of 'n' terms = (n/2){2a+(n-1)d}
Hence for first seven terms we have
10=(7/2){2a+(7-1)d} or 10 = 7a +21d
and for first 14 terms
27=(14/2){2a+(14-1)d} or 27 =14a +91d
Solving we get d=1/7 and a = 1....you can also use this method buddy!!
thnx
Welcome bro :)...thnx for marking brainliest
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1
Hope it will help you
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ya this is where i made the mistake thnx man
Don't you think that formula for sum is n/2[2a+(n-1)d]
Oh ya... Sorry for the mistake....
ya but i made the in putting the values usually happens with everone
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