Question

The third of an AP is 3 and the 11th term is -21.Find the first term and common difference

Answer 1

Hey Friend


Here is your answer

Answer 2

a3= a+2d=3 eq1
a11 =a+10d =-21 eq2
a+10d-a-2d=-21-3
8d=-24

d=-3
a1=a3-2d
3 -2×-3
3+ 6=9

hope u understand.