If the nth term of a sequence is 5+2n,then the sum of first 20 terms a

1.	If the nth term of a sequence is 5+2n,then the sum of first 20 terms and 30 terms are
Answer» ANSWER:S20=520 S30=1080 Step-by-step explanation: Tn=5+2n T1=a=5+2 (1)=5+2=7 T2=5+2 (2)=5+4=9 Common DIFFERENCE =T2-T1=9-7=2 Sn=n/2 (2A+(n-1)d) S20=20/2 (2 (7)+(20-1)2) = 10 (14+19 (2)) =10 (14+38) = 10 (52) =520// S30=30/2 (2 (7)+(30-1)2) = 15 (14+29 (2)) = 15 (14+58) = 15 (72) = 1080//

If the nth term of a sequence is 5+2n,then the sum of first 20 terms and 30 terms are

Answer»

ANSWER:S20=520

S30=1080

Step-by-step explanation:

Tn=5+2n

T1=a=5+2 (1)=5+2=7

T2=5+2 (2)=5+4=9

Common DIFFERENCE =T2-T1=9-7=2

Sn=n/2 (2A+(n-1)d)

S20=20/2 (2 (7)+(20-1)2) = 10 (14+19 (2)) =10 (14+38) = 10 (52) =520//

S30=30/2 (2 (7)+(30-1)2) = 15 (14+29 (2)) = 15 (14+58) = 15 (72) = 1080//

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If the nth term of a sequence is 5+2n,then the sum of first 20 terms and 30 terms are​

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If the nth term of a sequence is 5+2n,then the sum of first 20 terms and 30 terms are