RRB JE practice question
Find the value of 1³ + 2³ + 3³ + … + 17³.
From a RRB JE Quantitative Aptitude practice set · Quantitative Aptitude
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Correct answer: (B) 23409
Σn³ = [n(n + 1)/2]² = [17 × 18/2]² = 153² = 23409. (Note Σn³ equals the square of Σn.)
हिंदी में प्रश्न
1³ + 2³ + 3³ + … + 17³ का मान ज्ञात कीजिए।
उत्तर जाँचने के लिए किसी विकल्प पर टैप करें।
उत्तर और व्याख्या देखें
सही उत्तर: (B) 23409
Σn³ = [n(n + 1)/2]² = [17 × 18/2]² = 153² = 23409। (ध्यान दें Σn³, Σn के वर्ग के बराबर है।)
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