Question

find common difference and first term of Arithmetic progression 1,5,9,13.​

Answer 1

Step-by-step explanation:

First term, a = 1

Common difference, d = 5 - 1 = 4

Answer 2

The given sequence in AP is

$1,5,9,13$

We  need to first know the following things in order to do this question.

$a_n=a+(n-1)d$

where,

a = First term

n = Number of terms

d = Common difference

Now let us do the question.

For the first term

$a_1=1\\a_1=a+(1-1)d\\a_!=a\\a=1=a_1$

∴ $a=1$

For the second  term

$a_2=5\\a_2=1+(2-1)d=5\\a_2=1+d=5$

∴ $d=4$

Hence, the first term is 1 and the common difference is 4.