Question

What is the value of first term of the sequence an=n-1?​

Answer 1

Answer:

first term =1

Consider, n=1∴(n+1)thterm, i.e.

(1+1)th 2ndterm=(1)thterm+(1+1)

                                 =1+2

                                 =3.

For n=2,3rdterm

          =3+3=6

For n=3,4thterm

          =6+(3+1)=10

Similarly, 5thterm=10+5=15

& 6thterm=15+6=21

& The sequence is 1,3,6,10,15,21.

Answer 2

Given: an=n-1

We have to find the first term of the sequence.

The given problem is to solve in the following way:

We have,

an=n-1

Let's take n=1,

than,

put n=1 in the given equation

$an=n-1\\\\=a1=1-1\\=a1=0$

So, The first term of the sequence is

$=a1=1-1\\=a1=0$