If p^ th term of an Ap is q and q^th term is p.find its (p+q)^th term

1.	If p^ th term of an Ap is q and q^th term is p.find its (p+q)^th term
Answer» q = a + (p - 1)d ..... (i)p = a + (q - 1)d ...... (ii)q - p = (p - 1 - q + 1)d{tex}\\frac{{q - p}}{{p - q}} = d{/tex}{tex} \\Rightarrow d = - 1{/tex}Put the value of d in eq (i)q = a + (p - 1) (-1){tex} \\Rightarrow {/tex}\xa0q = a - p + 1{tex} \\Rightarrow {/tex}\xa0a = q + p - 1ap+q = a +(p + q - 1)d= (q + p - 1) + (p + q - 1) (-1)= q + p - 1 - p - q + 1= 0

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