nth term of an A.p is 4n+3 what is thesumoffirst25naturalnumberandfindoutthesumoffirst25terms
Answers
Answered by
1
We know that,
tn=a+(n-1)d
tn=4n+3. ....is given
therefore, a+(n-1)d=4n+3
Now we have calculate sum of first 25 natural numbers.
Therefore, n=25
now, Sn=n÷2[2a+(n-1)d]
putting the value we get,
S25=25÷2[2(4*25+3)] .....a+(n-1)d=4n+3 & n=25
S25=25*(100+3). ..…2&2get canceled
S25=25*103
S25=2575
Therefore sum of first 25 terms is 2575
tn=a+(n-1)d
tn=4n+3. ....is given
therefore, a+(n-1)d=4n+3
Now we have calculate sum of first 25 natural numbers.
Therefore, n=25
now, Sn=n÷2[2a+(n-1)d]
putting the value we get,
S25=25÷2[2(4*25+3)] .....a+(n-1)d=4n+3 & n=25
S25=25*(100+3). ..…2&2get canceled
S25=25*103
S25=2575
Therefore sum of first 25 terms is 2575
Similar questions