JEE Mains · Maths · STD 11 - 8. sequence and series
Let the positive integers be written in the form :
If the \(\mathrm{k}^{\text {th }}\) row contains exactly \(\mathrm{k}\) numbers for every natural number \(\mathrm{k}\), then the row in which the number \(5310\) will be, is .........
- A \(103\)
- B \(105\)
- C \(108\)
- D \(107\)
Answer & Solution
Correct Answer
(A) \(103\)
Step-by-step Solution
Detailed explanation
\( \mathrm{S}=1+2+4+7+\ldots \ldots+\mathrm{T}_{\mathrm{n}} \) \( \mathrm{S}=1+2+4+\ldots \ldots \) \( \mathrm{Tn}=1+1+2+3+\ldots \ldots+\left(\mathrm{T}_{\mathrm{n}}-\mathrm{T}_{\mathrm{n}-1}\right) \)…
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