Find the sum of first 25 terms of an AP whose nth term is given by ax=

1.	Find the sum of first 25 terms of an AP whose nth term is given by ax=3x+2
Answer» ax=3x+2a1=a=3(1)+2=5a2=a+d=3(2)+2=85+d=8-, d=3S25=25/2(10+24x3)=25/2(10+72)=25/2 x 82=25x41=1025\xa0 a,d,n, mil jaye toh sum wala formula mein put karo First put x=1 usse a1 aayega phir x=2put karna usse a2 aayega aur phir d nikal lena. 1025

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