Question

which of AP 121,117,113... is its first negative term?

Answer 1

Answer:

Step-by-step explanation:

121,117,113.......

a=121. d=-4

For a(n) be negative

a(n)<0

a+(n-1)d <0

121+(n-1)*(4)<0

For ans be negative

(n-1)(-4)>121

4n >(125)

n >125/4

n >31.25

n=32

Therefore the 31st term is the negative term

Verification

a(n)=a+(n-1)d

a(n)=121+(32-1)-4

a(n)=121+31*-4

a(n)=121-124

a (n)=-3

I hope it helps u

Answer 2

Let term nth

d=117-121=-4

a+(n-1)d =1

121+(n-1)×-4 =1
-4n+4=-120
4n=124
n=31

31th term is 1 .

so 1st negative term is

1-4=-3


so 1st negative term of this AP is 32nd