Question

if ninth and third term of ap are 4 and -8 which term is zero

Answer 1

Answer:

7th term

Step-by-step explanation:

9th term=4

a+8d=4 (1st eq)

3rd term=-8

a+2d=-8 (2nd eq)

2nd eq-1st eq

a+2d=-8

a+8d=4

(-) (-)

-6d=-12

d=2

subtitute 'd' in 1st eq

a+8(2)=4

a+16=4

a=4-16

a=-12

an=0

a+(n-1)d=an

-12+(n-1)2=0

-12+2n-2=0

-14+2n=0

2n=14

n=7

7th term of the A.P is 0

I hope this answer may help you