ARITHMETIC
PROGRESSIONS
4) Which of the following are APs ? If they form an AP, find the common difference d and write three more terms.
Sol:
a2
- a1
=
=
=
a3
- a2
=
=
=
a4
- a3
=
=
=
As difference is constant, the given list of numbers is an A.P.
a5
=
a4
+ d
=
=
=
=
a6
=
a5
+ d
=
=
=
=
a7
=
a6
+ d
=
=
=
=
a5, a6, a7
By adding d to a term we get a next term
In an AP difference between any two consecutive terms is constant
Exercise 5.1 4(xii)