Question

a2=13;a4=3 find a1,a3

Answer 1

a2= 13 ,a4= 3
a+d = 13. ,a+3d =3


a+d -(a+3d) = 13-3
a+d -a-3d= 10
-2d=10
d=-5


a+d =13
a-5 = 13
a= 18


a3 =a+2d
= 18 +2×-5
= 8
a=a1= 18

a