Question

We APs have the same common difference. The first term of one A.P. is 2 and that of the
other is 7. The difference between their 10" terms is the same as the difference between
their 21 terms, which is the same as the difference between any two correspondine
terms. Why?
INCERT EXEMPLARI
Thus,​

Answer 1

Answer:

USING AN FORMULA

Step-by-step explanation:

let  the ap common difference =  d  a1 = 7 and ti =2

A/Q

a10 - t10  = a21 - t21 [given]

LHS  a1 + 9d - t1 - 9d

            a1 - t1

= 7 - 2 = 5    

RHS

a21 - t21  =  a1 + 20d - t1 -20d

=a1 - t1 = 7 - 2 = 5

hence LHS = RHS