Question

What is the com.on diffrence of AP if nth term is (7n-1)??

Answer 1

$nth \: term = a_n = 7n - 1 \\ \\ first \: term, \: a_1 = 7 \times 1 - 1 = 7 - 1 = 6 \\ \\ second \: term, \: a_2 = 7 \times 2 - 1 = 14 - 1 = 13 \\ \\ common \: difference =d \\ \\ d = a_2 - a_1 = 13 - 6 = \boxed{7}$