Question

write down the first term in the sequence given by: T(n)=n^2+3

Answer 1

Some people call 'n' "zero" for the first term, others call 'n' "1".

-- If n=0 for the first term, then T(0) =  0² + 3  =  3 .

-- If n=1 for the first term, then  T(1) = 1² + 3  =  4 .

Answer 2

A sequence always starts with n as 1. So set n=1 and find T(n) or the first term.
T(n)=1^2+3
T(n)=1+3=4
Hope this helps.