Question

How many terms are there in AP 4,-1,-6.....-106

Answer 1

hey friend

here
a=4
and d=-5
an=-106
an=a+(n-1)d
4+(n-1)-5=-106
4-5n+5=-106
-5n+9+106=0
-5n=-115
n+115/5=>23

hope it helps you

Answer 2

Hey friend, ☺️ here is your answer ___________________________

First term, a1 = 4
Second term, a2 = - 1
Common difference, d = a2 - a1 = - 1 - 4 = - 5
Last term, an = - 106

an = a1 + (n - 1)d
-106 = 4 + (n - 1)*-5
-106 = 4 - 5n + 5
-106 = 9 - 5n
-5n = - 106 - 9
-5n = - 115
n = 23

Total number of terms = 23

Hope this helps you..