Question

Tn=2n+1 find the sum of first three terms

Answer 1

n=1
t1=2×1+1
t1=3

n=2
t2=2×2+1
t2=5

n=3
t3=2×3+1
t3=7

t1+t2+t3=15

Answer 2

here is ur answer
Tn=2n+1
T1=2×1+1
=2+1=3
T2=2×2+1
=4+1=5
T3=2×3+1
=6+1=7
there fore the first 3 terms are
3 , 5 and 7
the sum =3+5+7=15