यदि किसी समान्तर श्रेणी का \(S_n=3n^2+4n\) है तो (16)वें से (25)वें पदों का योग कितना होगा?
If \(S_n=3n^2+4n\) for an arithmetic progression, what is the sum from the (16)th to the (25)th terms?
Explanation opens after your attempt
C. (1240)
Concept
The required sum is \(S_{25}-S_{15}=1975-735=1240\). Exam tip: use the difference of cumulative sums for middle terms.
Why this answer is correct
The correct answer is C. (1240). The required sum is \(S_{25}-S_{15}=1975-735=1240\). Exam tip: use the difference of cumulative sums for middle terms.
Exam Tip
वांछित योग \(S_{25}-S_{15}=1975-735=1240\) है। परीक्षा में बीच के पदों के लिए कुल योगों का अंतर लें।
Login to save your score, XP, coins and progress.
