The sum of first 25 terms of an AP whose nth term is 2-3n, is

1.	The sum of first 25 terms of an AP whose nth term is 2-3n, is
Answer» Put n =1put n =2put n =3So, A.P. become s: -1 , -4 , -7, ........So, first term =a= -1Common difference d = -4-(-1)=-7-(-4)= -3Formula of sum of first n terms :\xa0Put n =25Hence the sum of first 25 terms of an AP is -925

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