How many terms or arithmetic progression (A.P.) 21, 18, 15, 12, .... must be taken to Give the sum zero ?
Created: 5 years ago |
Updated: 3 years ago
best des
এখানে, 21, 18, 15, 12,
১ম পদ, a = 21
সাধারণ অন্তর d = 18 - 21 = 3
সমষ্টি = n/2 { 2a + ( n - 1) d }
0 = n/2{ 2 × 21 + ( n - 1) ( - 3) }
0 = n/2 ( 42 - 3n + 3)
45n - 3n2 = 0
n = 15
Md Azizur Rahman
Founder of Satt
Related Question
View More
Created: 6 years ago |
Updated: 3 weeks ago
Created: 6 years ago |
Updated: 6 days ago
Created: 6 years ago |
Updated: 4 days ago
Created: 6 years ago |
Updated: 6 days ago
Created: 6 years ago |
Updated: 6 days ago
Promotion
Download Our Mobile Apps
