Question

write the first four terms of AP if sum of first n terms is 5n square + 3n​

Answer 1

hope it is helpful to yoy

Answer 2

Sum of first terms=First term

>>a=5*1*1+3*1=8 ; a=8

>>S4=5*4*4 + 3*4=4*(8*2+(4-1)d)/2

>>80+12=2*(16+3d)

>>92=32+6d

>>6d=60

>>d=10

AP 4 terms are : a,a+d,a+2d,a+3d=8,18,28,38