Sequence And Series Question 154

Question: If $ p $ times the $ p^{th} $ term of an A.P. is equal to $ q $ times the $ q^{th} $ term of an A.P., then $ {{(p+q)}^{th}} $ term is

[MP PET 1997; Karnataka CET 2002]

Options:

A) 0

B) 1

C) 2

D) 3

Show Answer

Answer:

Correct Answer: A

Solution:

$ p{a+(p-1),d}=q{a+(q-1),d} $
$ \Rightarrow $ $ a(p-q)+(p^{2}-q^{2}),d+(q-p),d=0 $
$ \Rightarrow $ $ (p-q){a+(p+q-1),d}=0 $
$ \Rightarrow $ $ a+(p+q-1),d=0 $
$ \Rightarrow $ $ {T_{p+q}}=0 $ , $ {\because \ p\ne q} $ .