Question

1. If a , b , c and d are in AP then c – b is ………………….

A) d – a B) d – b C) d – c D) None of these​

Answer 1

Step-by-step explanation:

a,b,c,d,e are in A.P

∴b=a+D

c=a+2D

d=a+3D

e=a+4D

Here D is the common difference substitute the values of b,c,d and e in the given expression.

a−4b+6c−4d+e

=a−4(a+D)+6(a+2D)−4(a+3D)+a+4D

=a−4a−4D+6a+12D−4a−12D+a+4D

=8a−8a

=0