यदि समानांतर श्रेढ़ी में \(a_4=19\) और \(a_7=31\) है, तो \(a_1\) क्या होगा?
If an arithmetic progression has \(a_4=19\) and \(a_7=31\), what is \(a_1\)?
Explanation opens after your attempt
B. (7)
Concept
The increase over three gaps is (12), so (d=4), then (a_1=19-3(4)=7). From middle terms first find the common difference.
Why this answer is correct
The correct answer is B. (7). The increase over three gaps is (12), so (d=4), then (a_1=19-3(4)=7). From middle terms first find the common difference.
Exam Tip
तीन अंतरों में वृद्धि (12) है इसलिए (d=4), फिर (a_1=19-3(4)=7)। बीच के पदों से पहले समान अंतर निकालें।
Login to save your score, XP, coins and progress.
