Question

The series (n – 1), (n – 2), (n – 3), …………… is a type of 

A) A.P

B) G.P

C) May be both

D) None

Answer 1

Correct option is (A) A.P.

\(a_1=n-1,a_2=n-2,a_3=n-3\)

\(a_2-a_1=(n-2)-(n-1)=-1,\)

\(a_3-a_2=(n-3)-(n-2)=-1\)

\(\because\) \(a_3-a_2=a_2-a_1\)

\(\therefore\) Sequence (n-1), (n-2), (n-3), …… is a type of A.P.

Answer 2

Correct option is A) A.P