Show that T1 , T2 , T3 , .... …
CBSE, JEE, NEET, CUET
Question Bank, Mock Tests, Exam Papers
NCERT Solutions, Sample Papers, Notes, Videos
Related Questions
Posted by Shraddha Bhadauriya 2 days, 19 hours ago
- 0 answers
Posted by Diksha Samant 22 hours ago
- 0 answers
Posted by Subhalaxmi Panda 3 days, 5 hours ago
- 0 answers
Posted by Rishi Jha 3 days, 21 hours ago
- 0 answers
Posted by Rohini Sharma 1 day, 5 hours ago
- 0 answers
Posted by Vivek Verma 1 day, 4 hours ago
- 0 answers
myCBSEguide
Trusted by 1 Crore+ Students
Test Generator
Create papers online. It's FREE.
CUET Mock Tests
75,000+ questions to practice only on myCBSEguide app
Rashmi Bajpayee 7 years, 2 months ago
Given: Tn = 9 - 5n
T1 = a = 9 - 5 x 1 = 9 - 5 = 4
T2 = 9 - 5 x 2 = 9 - 10 = -1
Therefore, d = -1 - 4 = -5
S15 = n/2[2a + (n - 1)d]
= 15/2[2 x 4 + (15 - 1) x (-5)]
= 15/2[8 - 70]
= 15/2 x [-62]
= -465
Therefore, the sum of 15 terms of given AP is -465.
0Thank You